NHC Halide Redn Supp Info · Carbohydrate Res. 1992, 230, 327–342. Supplementary Material (ESI)...
Transcript of NHC Halide Redn Supp Info · Carbohydrate Res. 1992, 230, 327–342. Supplementary Material (ESI)...
SUPPORTING INFORMATION
Radical reductions of alkyl halides bearing electron withdrawing
groups with N-heterocyclic carbene boranes
Shau-Hua Ueng,a,b Louis Fensterbank,a Emmanuel Lacôte,a Max Malacria,a and Dennis P. Curran*b
a Institut Parisien de Chimie Moléculaire (UMR CNRS 7201) UPMC Univ Paris 06, 4
place Jussieu, C. 229, 75005 Paris, France.
b University of Pittsburgh, Department of Chemistry,Pittsburgh, PA 15260, USA.
[email protected], [email protected], [email protected],
Table of Contents
General Remarks..................................................................................................... S2
Pilot Reductions of Adamantyl Halides ................................................................... S3
Experimental Procedures, Compound Characterization ........................................... S4
11B NMR Time-course Spectra.............................................................................. S12
Copies of Spectra .................................................................................................. S14
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General Remarks: Chemicals and solvents were purchased from commercial
suppliers and used as received. The benzene used for AIBN-initiated free radical
reactions was deoxygenated by passing a gentle stream of argon through for 20 min
before use. All flash column chromatography was performed with 230–400 mesh
silica gel purchased from Sorbent Technologies as the stationary phase. Proton (1H),
carbon (13C), and boron (11B) nuclear magnetic resonance spectra were measured on a
Bruker Avance 300 instrument at 300 MHz, 75 MHz, and 96.3 MHz, and Bruker
Avance spectrometer fitted with a BBFO probehead at 400, 100, and 128.4 MHz,
respectively. The chemical shifts in spectra were measured in parts per million (ppm)
on the delta (δ) scale relative to the resonance of the solvent peak (CDCl3 signal as
reference, 1H = 7.26 ppm, 13C = 77.0 ppm). 11B chemical shifts are given relative to
BF3•OEt2 (11B = 0 ppm). Unless noted, NMR spectra were recorded in CDCl3 at 300
K. The resonance of the carbene carbon center connected to boron could not be
observed because of the quadrupole broadening. The following abbreviations were
used to describe coupling: s = singlet; d = doublet; t = triplet; q = quartet; br = broad;
m = multiplet. Infrared (IR) spectra were recorded on a Nicolet Avatar 360 FT-IR
spectrometer as thin films (CH2Cl2) on NaCl plates and Bruker Tensor 27 ATR
diamant PIKE spectrometer. Low and high resolution mass spectra were obtained
on a Micromass Inc. Autospec instrument with E-B-E geometry and also recorded by
Structure et fonction de molecules bioactives (UMR 7613) of Université Pierre et
Marie Curie (electrospray source).
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Table S1. Pilot reductions of adamantyl halides with 3
XN
NBH3
PhH or tBuPh
H
entry X conditions time solvent [RX] T °C GC yield (%)
1 I Et3B/O2 (1 equiv) 2 h benzene (1 mL) 0.1 M rt 21%
2 I Et3B/O2 (6 equiv) 2 h benzene (1 mL) 0.1 M rt 32% (25% SM)
3 I AIBN (1 equiv) 2 h benzene (1 mL) 0.1 M 80°C 31% (15% SM)
4 I ACCN (1 equiv) 2 h benzene (1 mL) 0.1 M 110°C 64% (14% SM)
5 I ACCN (1 equiv) 2 h toluene (4 mL) 0.025
M 110°C 53% (20% SM) Pressure tube
6 I – 2 h toluene-d8 (0.5 mL) 0.1 M 110°C 9% (80% SM)
7 Br Et3B/O2 (1 equiv) 2 h benzene (1 mL) 0.1M rt 9%
8 Br Et3B/O2 (6 equiv) 2 h benzene (1 mL) 0.1 M rt 12% (82% SM)
9 Br AIBN (1 equiv) 2 h benzene (1 mL) 0.1M 80°C 2% (98% SM)
10 Br ACCN (1 equiv) 2 h toluene (4 mL) 0.025
M 110°C 48% (50% SM) pressure tube
11 Br ACCN (1 equiv) 2 h benzene (1 mL) 0.1 M 80°C 12% (88% SM)
12 Br ACCN (1 equiv) 2 h benzene (1 mL) 0.1 M 80°C 27% (78% SM)
13 Br tBuOOtBu hν 2 h
benzene (0.1 mL)
tert-butylbenzene (0.5 mL)
0.08 M ~60 °C 60% (NMR tube)
14 Br No tBuOOtBu 2 h
benzene (0.1 mL)
tert-butylbenzene (0.5 mL)
0.08 M ~60 °C 0%
ACCN is 1,1'-azobis(cyclohexane-1-carbonitrile)
Dr. Julien Monot also contributed to these results.
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OI O
HOO
O H
1,2:5,6-Di-O-isopropylidene-3-iodo-α-D-glucofuranose (5a): Iodine (0.58 g, 2.28
mmol) was added to the solution of diacetone-α-D-glucose (0.5 g, 1.9 mmol),
triphenylphosphine (0.6 g, 2.28 mmol), and imidazole (0.26 g, 3.8 mmol) in of
toluene (12 mL). The brown mixture was reflux for 3 h, and followed by the addition
of sat'd NaHCO3 (aq) (10 mL). The byphase system was partitioned between ethyl ether
(70 mL ) and sat'd NaHCO3 (aq) solution (30 mL). The org. layer was washed with
sat'd Na2S2O3 (aq) (30 mL), water (30 mL) and brine (30 mL), dried (MgSO4), and
concentrated to give a yellow oil. The yellow oil was purified by flash
chromatography (SiO2, elution with hexane : ethyl acetate = 85 : 15) to give the
desired iodide 5a as a white solid (0.38 g, 54 %). 1H NMR (CDCl3, 300 MHz): δ 5.82
(d, J = 3.6 Hz, 1H), 4.61 (t, J = 4.1 Hz, 1H), 4.40–4.23 (m, 2H), 4.20–4.04 (m, 2H),
3.77 (dd, J = 9.9, 4.5 Hz, 1H), 1.56 (s, 3H), 1.50 (s, 3H), 1.38 (s, 6H). Data
correspond to those reported in the literature.1
OBr O
HOO
O H
1,2:5,6-Di-O-isopropylidene-3-bromo-α-D-glucofuranose (5b): Carbon tetra-
bromide (0.76 g, 2.28 mmol) was added to the solution of diacetone-α-D-glucose (0.5
g, 1.9 mmol), triphenylphosphine (0.6 g, 2.28 mmol), and imidazole (0.26 g, 3.8
mmol) in toluene (12 mL). The brown mixture was reflux for 3 h, and followed by the
addition of sat'd NaHCO3 (aq) (10 mL). The byphase system was partitioned between
ethyl ether (70 mL) and 30 mL of sat'd NaHCO3 (aq) solution. The org. layer was 1 Kunz, H.; Schmidt, P. Liebigs Ann. Chem. 1982, 1245–1260.
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washed with sat'd Na2S2O3 (aq) (30 mL), water (30 mL) and brine (30 mL), dried
(MgSO4), and concentrated to give a yellow oil. The yellow oil was purified by flash
chromatography (SiO2, elution with hexane : ethyl acetate = 8 : 2) to give the desired
iodide 5b as a white solid (0.17 g, 28 %). 1H NMR (CDCl3, 300 MHz): δ 5.75 (d, J =
3.6 Hz, 1H), 4.62 (t, J = 4.1 Hz, 1H), 4.35–4.23 (m, 1H), 4.15 (dd, J = 9.6, 3.3 Hz),
4.11–3.95 (m, 2H), 3.83 (dd, J = 9.9, 4,5 Hz, 1H), 1.51 (s, 3H), 1.41 (s, 3H), 1.32 (s,
6H). Data correspond to those reported in the literature.2
OO
HOO
O H
1,2:5,6-Di-O-isopropylidene-3-deoxy-α-D-glucofuranose (6): This was prepared
by the conditions listed in Table 1 with 0.1 mmol of starting halides 5a and 5b;
product 6 was isolated (hexane : ethyl acetate = 85 : 15, 10.0−19.3 mg, 41−79 %) as a
colorless liquid. 1H NMR (CDCl3, 300 MHz): δ 5.81 (d, J = 3.7 Hz, 1H), 4.75 (t, J =
4.2 Hz, 1H), 4.23−4.03 (m, 3H), 3.87−3.75 (m, 1H), 2.18 (dd, J = 13.6, 4.2 Hz, 1H),
1.76 (ddd, J = 13.6, 9.6, 4.2 Hz, 1H), 1.50 (s, 3H), 1.42 (s, 3H), 1.35 (s, 3H), 1.31 (s,
3H). Data correspond to those reported in the literature.1
OI
AcOAcO
OAcOAc
1,2,3,4-Tetra-O-acetyl-6-iodo-β-D-glucopyranose (9): This was prepared following
the procedure that described the synthesis of 5a with 1,2,3,4-tetra-O-acetyl-
β-D-glucopyranose (0.2 g, 0.57 mmol). The crude product was purified by flash
chromatography (SiO2, elution with hexane : ethyl acetate = 7 : 3) to give iodide 9 as
a white solid (0.187 g, 72 %). 1H NMR (CDCl3, 300 MHz): δ 5.75 (d, J = 8.1 Hz, 1H), 2 Hodosi, G.; Podányi, B.; Kuszmann, J. Carbohydrate Res. 1992, 230, 327–342.
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5.26 (t, J = 9.3 Hz, 1H), 5.13 (dd, J = 9.3, 8.1 Hz, 1H), 4.99 (t, J = 9.3 Hz, 1H),
3.65−3.51 (m, 1H), 3.33 (dd, J = 11.1, 3.0 Hz, 1H), 3.16 (dd, J = 11.1, 6.3 Hz, 1H),
2.13 (s, 3H), 2.06 (s, 3H), 2.03 (s, 3H), 2.01 (s, 3H). Data correspond to those
reported in the literature.3
OAcOAcO
OAcOAc
1,2,3,4-Tetra-O-acetyl-6-deoxy-β-D-glucopyranose (10): This was prepared by the
conditions listed in Table 2 with 0.1 mmol of starting halides 9; product 10 was
isolated (hexane : ethyl acetate = 7 : 3, 22.2−23.6 mg, 67−71 %) as a colorless oil. 1H
NMR (CDCl3, 300 MHz): δ 5.68 (d, J = 8.1 Hz, 1H), 5.19 (t, J = 9.5 Hz, 1H), 5.09 (t,
J = 9.0 Hz, 1H), 4.84 (t, J = 9.5 Hz, 1H), 3.78−3.63 (m, 1H), 2.14 (s, 3H), 2.04 (s, 3H),
2.01 (s, 3H), 2.00 (s, 3H), 1.23 (d, J = 6.3 Hz, 3H). Data correspond to those reported
in the literature.4
O O
I
3-Iodo-3,4-dihydrocoumarin (11): 1H NMR (CDCl3, 300 MHz): δ 7.42−7.32 (m,
1H), 7.25−7.15 (m, 2H), 7.15−7.08 (m, 1H), 4.95 (dd, J = 4.5, 3.0 Hz, 1H), 3.49 (dd, J
= 17.4, 4.5 Hz, 1H), 3.11 (dd, J = 17.4, 3 Hz, 1H). Data correspond to those reported
in the literature.5
O O 3,4-Dihydrocoumarin (12): A solution of 3-iodo-3,4-dihydrocoumarin 11 (27.4 mg,
3 Kaszynski, P.; McMurdie, N. D.; Michl, J. J. Org. Chem. 1991, 56, 307–316. 4 Zercher, C. K.; Fedor, L. R. Carbohydrate Res. 1987, 165, 299–305. 5 Murakata, M.; Jono, T.; Shoji, T.; Moriy, A.; Shirai, Y. Tetrahedron: Asymm. 2008, 19, 2479–2483.
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0.1 mmol) and dimethylimidazolylidene borane 3 (11.0 mg, 0.1 mmol) in of
benzene-d6 (1 mL ) was placed in a NMR tube, and the reaction progress was
monitored by 1H NMR spectroscopy until the conversion of the starting material was
complete. 1,3,5-Trimethoxybenzene (11.8 mg, 0.07 mmol) was added to the reaction
solution as the internal standard, and the yield was determined by 1H NMR
spectroscopy analysis (70 %). The resulting product was purified by flash
chromatography (SiO2, pentane : ethyl ether = 8 : 2) to give 12 as a colorless oil (8.9
mg, 60 %). 1H NMR (CDCl3, 300 MHz): δ 7.32−7.15 (m, 2H), 7.11 (d, J = 7.5 Hz,
1H), 7.05 (d, J = 8.7 Hz, 1H), 3.01 (dd, J = 7.5, 6.9 Hz, 2H), 2.79 (dd, J = 6.9, 5.4 Hz,
2H), Data correspond to those reported in the literature.6
TsN
I
TsN
Cl
TsHN
I II 15a
KOHBu4NBr
1-Bromo-2-chloroethane
THF, rt
73 %
NaI
DMF, 80 oC
55 %
N-Allyl-N-(2-chloro-ethyl)-4-methyl-benzenesulfonamide (II): Tetrabutyl-
ammonium bromide (0.6 mmol) was added to a solution of I (6.0 mmol), potassium
hydroxide (9.0 mmol), and 1-bromo-2-chloroethane (9.0 mmol) in THF (30 mL). The
white mixture was stirred at room temperature for 16 h, and then partitioned between
ethyl ether (100 mL) and water (40 mL). The organic layer was washed with water
(40 mL), brine (40 mL), dried (MgSO4), and concentrated. The crude product was
purified by flash chromatography (SiO2, ethyl acetate : pentane = 1 : 9 then 2 : 8) to
afford the chloride II as a colorless oil (1.2 g, 73 %). IR (neat, cm-1) νmax 2930, 1710,
1598, 1451, 1340, 1156, 1091; 1H NMR (CDCl3, 400 MHz) δ 7.71 (d, J = 8.3 Hz, 2H),
7.32 (d, J = 8.3 Hz, 2H), 5.75−5.57 (m, 1H), 5.25−5.12 (m, 2H), 3.83 (d, J = 7.5 Hz,
6 Hwu, J. R.; Wein, Y. S.; Leu, Y.-J. J. Org. Chem. 1996, 61, 1493–1499.
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2H), 3.62 (t, J = 7.4 Hz, 2H), 3.37 (t, J = 7.4 Hz, 2H), 2.44 (s, 3H); 13C NMR (CDCl3,
100 MHz) δ 144.4, 137.0, 133.5, 130.5, 127.9, 120.3, 52.8, 49.5, 42.4, 22.2; HRMS
calcd. for C12H16O2NClNaS ([M+Na]+) 296.0482, found 296.0483.
N-Allyl-N-(2-iodo-ethyl)-4-methyl-benzenesulfonamide (15a): Sodium iodide (15
mmol) was added to a solution of chloride II (3.0 mmol) in DMF (7 mL). The
colorless solution was stirred at 80 oC for 16 h, and then cooled to room temperature.
The white resulting mixture was partitioned between ethyl ether (100 mL) and water
(40 mL). The organic layer was washed with water (40 mL), brine (40 mL), dried
(MgSO4), and concentrated. The crude product was purified by flash chromatography
(SiO2, ethyl acetate : pentane = 1 : 9) to afford the iodide 15a as a colorless oil (0.6 g,
55 %). 1H NMR (CDCl3, 400 MHz) δ 7.76−7.65 (m, 2H), 7.32 (d, J = 8.5 Hz, 2H),
5.76−5.60 (m, 1H), 5.27−5.12 (m, 2H), 3.85−3.73 (m, 2H), 3.50−3.35 (m, 2H),
3.30−3.15 (m, 2H), 2.44 (s, 3H). Data correspond to those reported in the literature.7
N-Allyl-N-(2-bromo-ethyl)-4-methyl-benzenesulfonamide (15b): Bromide 15b was
prepared following established procedures.8,9 1H NMR (CDCl3, 400 MHz) δ 7.70 (d, J
= 8.0 Hz, 2H), 7.32 (d, J = 8.0 Hz, 2H), 5.76−5.60 (m, 1H), 5.26−5.13 (m, 2H), 3.81
(d, J = 6.6 Hz, 2H), 3.50−3.35 (m, 4H), 2.43 (s, 3H). Data correspond to those
reported in the literature.9
TsN
3-Methyl-1-(toluene-4-sulfonyl)-pyrrolidine (16): This was prepared by the
7 Ohmiya, H.; Wakabayashi, K.; Yorimitsu, H.; Oshima, K. Tetrahedron 2006, 62, 2207−2213. 8 Miyata, O.; Ozawa, Y.; Ninomiya, I.; Naito, T. Tetrahedron 2000, 56, 6199−6208. 9 Rai, K. M. L.; Hassner, A. Heterocycles 1990, 30, 817.
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conditions listed in Table 2 with 0.1 mmol of corresponding substrate; product 16 was
isolated (pentane : ethyl acetate = 9 : 1 then 8 : 2) as a colorless liquid. 1H NMR
(CDCl3, 400 MHz) δ 7.70 (d, J = 8.4 Hz, 2H), 7.31 (d, J = 8.4 Hz, 2H), 3.42 (dd, J =
9.6, 7.2 Hz, 1H), 3.38−3.30 (m, 1H), 3.28−3.15 (m, 1H), 2.74 (dd, J = 9.6, 7.9 Hz,
1H), 2.43 (s, 3H), 2.16−2.05 (m, 1H), 1.95−1.80 (m, 1H), 1.42−1.28 (m, 1H), 0.91 (d,
J = 6.6 Hz, 3H). Data correspond to those reported in the literature.10
TsN
Br
O
N-Allyl-N-(2-bromo-acetyl)-4-methyl-benzenesulfonamide (17): NaH (60 % in
mineral oil) (92 mg, 2.31 mmol) was added to the solution of I (0.325 g, 1.54 mmol)
in THF (10 mL) at room temperature in one portion, before the addition of
bromoacetyl bromide (0.37 g, 1.85 mmol). The yellow mixture was stirred at room
temperature for 18 h, and then the yellow reaction mixture was partitioned between of
ethyl ether (70 mL) and water (30 mL). The org. layer was washed with water (30
mL), brine (30 mL), dried (MgSO4), and concentrated to give a yellow oil. The yellow
oil was purified by flash chromatography (SiO2, ethyl acetate : pentane = 1 : 9) to give
the desired product 17 as a colorless oil (0.25 g, 49 %). 1H NMR (CDCl3, 300 MHz) δ
7.83 (d, J = 8.1 Hz, 2H), 7.36 (d, J = 8.1 Hz, 2H), 5.95−5.75 (m, 1H), 5.33−5.18 (m,
2H), 4.46 (d, J = 6.6 Hz, 2H), 4.23 (s, 2H), 2.46 (s, 3H). Data correspond to those
reported in the literature.11
10 Tang, J.; Shinokubo, H.; Oshima, K. Tetrahedron 1999, 55, 1893−1904. 11 Ozaki, S.; Matsushita, H.; Ohmori, H. J. Chem. Soc., Perkin Trans. 1 1993, 2339–2344.
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TsNO
4-Methyl-1-(toluene-4-sulfonyl)-pyrrolidin-2-one (18): This was prepared by the
conditions listed in Table 2 with 0.1 mmol of 17; product 18 was isolated (hexane :
ethyl acetate = 9 : 1 then 7 : 3, 2.8−10.6 mg, 11−42 %) as a colorless oil. 1H NMR
(CDCl3, 300 MHz) δ 7.91 (d, J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz, 2H), 4.03 (dd, J =
9.9, 7.2 Hz, 1H), 3.41 (dd, J = 9.9, 6.3 Hz, 1H), 2.57 (dd, J = 16.6, 8.1 Hz, 1H),
2.52−2.38 (m overlapped with s at 2.44, 4H), 2.06 (dd, J = 16.6, 7.2 Hz, 1H), 1.09 (d,
J = 6.6 Hz, 3H). Data correspond to those reported in the literature.11
TsNO
N-Acetyl-N-allyl-4-methyl-benzenesulfonamide (19): This was prepared by the
conditions listed in Table 2 with 0.1 mmol of 17; product 19 was isolated (hexane :
ethyl acetate = 9 : 1 then 7 : 3, 6.8−14.7 mg, 27−58 %) as a colorless oil. 1H NMR
(CDCl3, 300 MHz) δ 7.81 (d, J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz, 2H), 5.98−5.80 (m,
1H), 5.33−5.20 (m, 2H), 4.46 (dt, J = 5.7, 1.5 Hz, 2H), 2.44 (s, 3H), 2.29 (s, 3H). Data
correspond to those reported in the literature.11
TsNO
Br
N-Allyl-N-(2-bromo-propionyl)-4-methyl-benzenesulfonamide (20): This was
prepared following the procedure described the synthesis of 17 with I (1.54 mmol)
and of 2-bromopropionyl bromide (1.85 mmol). The crude product was purified by
flash chromatography (SiO2, ethyl acetate : pentane = 15 : 85) to give the desired
product 20 as a white solid (0.38 g, 71 %). 1H NMR (CDCl3, 300 MHz) δ 7.87 (d, J =
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8.1 Hz, 2H), 7.35 (d, J = 8.1 Hz, 2H), 6.00−5.83 (m, 1H), 5.33−5.20 (m, 2H), 4.86 (q,
J = 6.6 Hz, 1H), 4.70 (dd, J = 17.4, 4.2 Hz, 1H), 4.41 (dd, J = 17.4, 5.4 Hz, 1H), 2.45
(s, 3H), 1.74 (d, J = 6.6 Hz, 3H). Data correspond to those reported in the literature.12
TsNO
trans-3,4-Dimethyl-1-(toluene-4-sulfonyl)-pyrrolidin-2-one (trans-21): This was
prepared by the conditions listed in Table 2 with 0.1 mmol of 20; product 21 was
isolated (hexane : ethyl acetate = 9 : 1 then 7 : 3, 6.8−14.7 mg, 36−44 %) as a
colorless oil. 1H NMR (DMSO-d6, 300 MHz) δ 7.83 (d, J = 8.1 Hz, 2H), 7.44 (d, J =
8.1 Hz, 2H), 3.98 (dd, J = 9.3, 7.5 Hz, 1H), 3.28 (t, J = 9.6 Hz, 1H), 2.40 (s, 3H),
2.22−2.10 (m, 1H), 2.03−1.85 (m, 1H), 1.03 (d, J = 6.3 Hz, 3H), 0.96 (d, J = 6.9 Hz,
3H). Data correspond to those reported in the literature.12
TsNO
N-Allyl-4-methyl-N-propionyl-benzenesulfonamide (22): Following corresponding
conditions with 0.1 mmol of 20, a mixture of compounds 22, I, and rest of the AIBN
was isolated (hexane : ethyl acetate = 9 : 1 then 7 : 3) as a colorless oil. The percent
yield of amide 22 was determined by 1H NMR spectroscopy analysis as 17–28 %. 1H
NMR (CDCl3, 300 MHz) δ 7.82 (d, J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz, 2H),
5.98–5.82 (m, 1H), 5.33–5.20 (m, 2H), 4.48 (d, J = 8.4 Hz, 2H), 2.56 (q, J = 7.3 Hz,
2H), 2.45 (s, 3H), 1.04 (t, J = 7.3 Hz, 3H). Data correspond to those reported in the
literature.12
12 Ozaki, S.; Matsushita, H.; Emoto, M.; Ohmori, H. Chem. Pharm. Bull. 1995, 43, 32–36.
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0 -20 -40 -60 ppm
(a)
(b)
N
NBH3
I2 (0.5 equiv)
N
NBH2I
unidentifiedspecies
NaBH484 %
3 23a
Figure S1. Partial 11B NMR spectra [96.3 MHz, Benzene-d6, 298 K] displaying (a-b)
the formation of the 1,3-dimethylimidazol-2-ylidene borane 3 from monoiodide
intermediate 23a under the treatment with NaBH4 over time—(a) 0 min, (b) 30 min,
after addition of 2 equiv of NaBH4.
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0 -20 -40 -60 ppm
(a)
(b)
(c)
(d)
N
NBH2
h!, 15 mind-Benzene, 60 oC
OBr
O
N
NBH2Br
NaBH4
77 %
3 23b
Figure S2. Partial 11B NMR spectra [96.3 MHz, Benzene-d6, 298 K] displaying (a-d)
the formation of the 1,3-dimethylimidazol-2-ylidene borane 3 from monobromide
intermediate 23b under the treatment with NaBH4 over time and the loading scale of
NaBH4—(a) 0 min, after irradiation for 15 min (b) 10 min, 0.5 equiv of NaBH4 (c) 20
min, 1.5 equiv of NaBH4, and (d) 180 min, 2 equiv of NaBH4.
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OI O
HOO
O H
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.378
1.498
1.560
1.567
3.748
3.763
3.781
3.796
4.042
4.065
4.070
4.093
4.115
4.136
4.144
4.164
4.242
4.255
4.276
4.288
4.304
4.317
4.326
4.339
4.347
4.593
4.607
4.620
5.818
5.830
7.260
6.88
3.64
5.55
1.07
2.32
0.60
0.74
0.88
1.05
1.00
shu2099b, 08−19−09, 301bSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
OBr O
HOO
O H
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.316
1.414
1.513
3.810
3.825
3.843
3.858
3.975
3.999
4.003
4.027
4.034
4.055
4.063
4.084
4.130
4.142
4.163
4.174
4.269
4.280
4.291
4.303
4.313
4.325
4.604
4.617
4.631
5.745
5.757
7.260
6.98
3.41
3.27
1.14
2.40
1.10
1.10
1.06
1.00
shu2100a, 08−20−09, 301bSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
OO
HOO
O H
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.362
1.397
1.416
1.430
1.450
1.484
1.502
1.518
1.711
1.727
1.744
1.756
1.760
1.772
1.789
1.805
2.146
2.160
2.192
2.205
3.777
3.798
3.806
3.816
3.823
3.831
3.845
4.065
4.071
4.086
4.103
4.112
4.114
4.126
4.130
4.144
4.151
4.156
4.170
4.189
4.731
4.745
4.760
5.783
5.800
5.813
7.259
4.23
2.97
3.37
3.35
1.21
1.06
1.10
3.31
1.04
1.00
shu2040a, 06−25−09, 301bSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
OI
AcOAcO
OAcOAc
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.577
2.014
2.033
2.063
2.131
3.129
3.151
3.167
3.188
3.302
3.312
3.339
3.349
3.534
3.544
3.555
3.566
3.576
3.587
3.597
4.957
4.988
5.019
5.102
5.130
5.134
5.161
5.224
5.255
5.286
5.734
5.761
7.261
3.21
3.00
3.14
3.09
1.08
1.08
1.08
0.98
0.97
1.02
1.00
shu3035a, 11−06−09, 301aSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
OAcOAcO
OAcOAc
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.219
1.240
1.267
1.627
1.719
1.874
1.977
1.995
2.013
2.035
2.083
2.094
2.140
3.654
3.674
3.695
3.707
3.727
4.810
4.842
4.873
5.059
5.091
5.119
5.163
5.194
5.226
5.665
5.692
7.243
7.258
7.268
7.394
3.56
2.93
2.96
2.96
2.61
1.01
0.98
1.04
1.08
1.00
shu3080a, 11−25−09, 301bSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
O O
I
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.547
3.072
3.082
3.130
3.140
3.449
3.452
3.464
3.467
3.507
3.522
3.525
4.938
4.947
4.952
4.962
7.103
7.129
7.153
7.157
7.178
7.182
7.195
7.197
7.200
7.203
7.220
7.230
7.248
7.258
7.307
7.325
7.328
7.335
7.346
7.352
1.11
1.12
1.00
1.09
2.21
1.06
shu3045b, 11−11−09, 301bSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
O O
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.252
1.431
1.574
2.772
2.794
2.800
2.820
2.989
3.014
3.037
7.043
7.071
7.100
7.125
7.189
7.212
7.233
7.261
7.284
2.00
2.10
1.59
1.96
shu3094a, 12−02−09, 301aSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
1.94
89
1.97
03
1.00
00
2.02
23
2.00
83
2.01
46
2.02
58
2.97
39
Inte
gral
7.71
977.
7148
7.70
337.
6989
7.33
017.
3285
7.30
887.
2600
5.71
935.
7034
5.69
525.
6869
5.67
875.
6765
5.66
235.
6601
5.65
135.
6453
5.64
375.
6354
5.61
905.
2229
5.21
965.
2163
5.21
305.
2059
5.20
315.
1999
5.19
715.
1790
5.17
575.
1725
3.83
883.
8361
3.83
343.
8230
3.81
973.
8169
3.63
673.
6186
3.61
583.
5994
3.39
183.
3726
3.35
452.
4351
1.55
90
(ppm)0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0
shu2112a
TsN
Cl
Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
shu2112a
144.
3512
137.
0253
133.
5209
130.
5134
127.
8830
120.
3429
77.9
984
77.6
814
77.3
643
52.8
076
49.4
746
42.4
229
22.1
931
(ppm)020406080100120140160180200220240260
TsN
Cl
Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
1.90
11
2.05
42
1.00
00
2.00
97
1.83
80
1.85
641.
8332
2.88
48
Inte
gral
7.72
137.
7120
7.70
767.
7005
7.69
567.
6912
7.33
127.
3296
7.30
997.
2605
5.71
605.
6996
5.69
135.
6886
5.67
495.
6727
5.66
395.
6480
5.63
165.
2985
5.21
635.
2130
5.20
925.
2042
5.20
105.
1982
5.19
495.
1763
5.17
305.
1703
3.80
383.
7901
3.78
733.
4449
3.42
683.
4202
3.40
443.
2559
3.23
893.
2350
3.23
293.
2153
3.21
372.
4367
1.55
19
(ppm)0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0
shu2117c
TsN
I
Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
2.00
00
2.02
39
1.00
54
2.04
64
2.00
55
4.18
70
3.09
18
Inte
gral
7.71
377.
6928
7.32
967.
3099
7.25
89
5.71
875.
7023
5.69
415.
6864
5.67
765.
6765
5.65
965.
6508
5.64
315.
6349
5.61
85
5.21
855.
2157
5.20
265.
2010
5.17
52
3.81
753.
8010
3.47
613.
4657
3.45
153.
4471
3.43
503.
4246
3.41
153.
3939
3.38
302.
4340
(ppm)0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0
shubromide
TsN
Br
Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
2.00
00
1.98
46
1.01
771.
0389
1.04
35
0.97
24
2.99
62
1.00
67
1.05
82
1.13
21
2.94
85
Inte
gral
7.71
647.
6956
7.32
197.
3203
7.30
167.
3005
7.26
00
3.43
723.
4191
3.41
313.
3950
3.36
443.
3539
3.34
353.
3397
3.33
313.
3293
3.31
943.
3085
3.24
273.
2241
3.22
193.
2181
3.20
383.
1994
3.19
723.
1792
2.76
332.
7436
2.73
922.
7195
2.42
582.
1381
2.11
842.
1009
2.08
171.
9343
1.92
391.
9168
1.90
531.
9003
1.89
271.
8866
1.87
571.
8691
1.85
811.
3924
1.37
161.
3612
1.35
081.
3409
1.33
001.
3196
1.29
871.
2505
0.91
740.
9108
0.90
09
(ppm)0.00.51.01.52.02.53.03.54.04.55.05.56.06.57.07.58.0
shu2122c
1.01
77
1.03
89
1.04
35
0.97
24
Inte
gral
3.41
913.
4131
3.39
503.
3644
3.35
393.
3435
3.33
973.
3331
3.32
933.
3194
3.30
853.
2427
3.22
413.
2219
3.21
813.
2038
3.19
943.
1972
3.17
922.
7633
2.74
362.
7392
2.71
95
(ppm)2.83.03.23.43.63.8
TsN
Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
TsN
Br
O
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.560
2.044
2.455
4.225
4.449
4.453
4.457
4.468
4.471
5.220
5.222
5.227
5.232
5.253
5.256
5.289
5.293
5.298
5.785
5.803
5.820
5.837
5.856
5.860
5.877
5.894
5.913
7.259
7.317
7.343
7.370
7.821
7.848
7.893
7.921
3.72
2.31
2.50
2.43
1.00
2.22
2.00
shu3077a, 11−24−09, 301aSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
TsNO
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.079
1.101
1.248
1.390
1.600
2.022
2.046
2.077
2.101
2.435
2.472
2.495
2.516
2.525
2.551
2.580
2.607
3.383
3.404
3.416
3.437
3.629
3.997
4.021
4.030
4.054
7.260
7.319
7.346
7.900
7.923
7.928
2.97
1.06
4.07
1.62
1.03
1.00
2.35
2.16
shu3104b, 12−09−09, 301Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
TsNO
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm2.290
2.440
4.445
4.450
4.454
4.463
4.468
4.473
5.219
5.223
5.249
5.252
5.257
5.301
5.306
5.309
5.816
5.834
5.850
5.852
5.868
5.873
5.887
5.891
5.907
5.910
5.925
5.944
7.259
7.316
7.318
7.345
7.784
7.790
7.796
3.09
3.24
2.06
2.06
1.00
2.11
2.00
shu3097a, 12−03−09, 301bSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
TsNO
Br
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.550
1.732
1.754
2.450
4.094
4.118
4.286
4.307
4.371
4.389
4.429
4.447
4.664
4.670
4.673
4.679
4.721
4.728
4.737
4.742
4.822
4.844
4.866
4.888
5.200
5.236
5.273
5.291
5.301
5.855
5.872
5.889
5.907
5.912
5.924
5.929
5.947
5.964
5.981
7.261
7.333
7.360
7.785
3.62
3.93
0.21
1.24
1.24
1.09
2.53
1.00
2.46
0.09
1.85
0.33
shu3044c, 11−12−09, 301aSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
TsNO
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
0.945
0.968
1.021
1.042
1.904
1.916
1.927
1.938
1.948
1.960
1.962
1.971
1.995
2.102
2.125
2.139
2.148
2.162
2.171
2.185
2.379
2.401
2.493
2.498
2.504
3.250
3.282
3.302
3.314
3.345
3.393
3.951
3.976
3.982
4.007
7.426
7.453
7.817
7.845
3.05
3.09
1.03
1.02
3.38
1.27
1.03
2.19
2.00
shu3071b_2, 11−24−09, 301aSupplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011
TsNO
+ TsHN
8.0 7.5 7.0 6.5 6.0 5.5 5.0 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 ppm
1.018
1.042
1.066
1.093
1.117
1.141
1.248
1.500
1.542
1.568
1.666
1.674
1.722
1.741
1.756
1.774
1.940
2.411
2.435
2.447
2.528
2.552
2.576
2.601
4.281
4.302
4.463
4.468
4.473
4.481
4.486
4.491
5.193
5.197
5.223
5.227
5.240
5.245
5.249
5.257
5.261
5.297
5.302
5.306
5.845
5.879
7.258
7.312
7.339
7.803
7.831
7.890
7.896
7.912
7.918
3.18
35.5
1
6.49
1.93
1.05
1.96
3.06
1.43
4.23
2.00
2.06
shu3071a, 11−21−09, 301Supplementary Material (ESI) for Organic & Biomolecular ChemistryThis journal is (c) The Royal Society of Chemistry 2011