E. B. Benetskiy, C. Bolm / Tetrahedron: Asymmetry 22 (2011) 373–378
377
under argon. Aniline and triethylamine were distilled over
(17), 140 (76), 125 (28). Anal. Calcd for C18H22N3OPS: C, 60.15; H,
6.17; N, 11.69. Found: C, 60.10; H, 6.01; N, 11.57.
KOH and then over
a small amount of LiAlH4 before use.
Phosphorylating reagents 1a6,9 and 1b,11 (S)- and (R)-N-benzyl-2-
methylpropane-2-sulfinamides,18 S,S-diphenylsulfoximine,19 (S)-
4.3.4. (2R,5S)-2-(S,S-Diphenylsulfonimidoyl)-3-phenyl-1,3-
diaza-2-phosphabicyclo[3.3.0]-octane 4
and (R)-S-methyl-S-phenylsulfoximines,20 [Pd(allyl)Cl]2,21 and
22
[Rh(COD)2]BF4
were prepared as described earlier. Starting
Yield: 88% as a white solid; mp 125–127 °C (from toluene).
substrates 10,21 14,23 16a–c24–27 were synthesized following the
½
a 2D2
ꢁ
¼ ꢀ151:6 (c 1.0, CHCl3). 1H NMR (400 MHz, CDCl3): d 1.56–
published procedures.
1.64 (m, 1H), 1.72–1.79 (m, 2H), 1.99–2.07 (m, 1H), 3.07–3.28
(m, 3H), 3.69–3.73 (m, 1H), 4.25–4.31 (m, 1H), 6.72 (t, 1H,
3J = 7.2 Hz), 6.86–6.89 (m, 2H), 7.09–7.13 (m, 2H), 7.32–7.37 (m,
4H), 7.39–7.43 (m, 2H), 7.81–7.86 (m, 4H). 13C NMR (100 MHz,
CDCl3): d 26.2 (d, 3J = 5.8 Hz), 33.3 (s), 49.6 (d, 2J = 34.4 Hz), 52.6
(d, 2J = 7.7 Hz), 63.9 (d, 2J = 8.6 Hz), 115.9 (d, 3J = 13.6 Hz), 118.1
(s), 127.6 (s), 127.8 (s), 128.6 (s), 128.7 (s), 128.8 (s), 131.9 (s),
132.0 (s), 143.1 (s), 143.5 (s), 145.8 (d, 2J = 12.5 Hz) (major epimer).
MS (EI, 70 eV): m/z (I, %): 421 (24), 344 (100), 202 (43). Anal. Calcd
for C23H24N3OPS: C, 65.54; H, 5.74; N, 9.97. Found: C, 65.61; H,
5.89; N, 9.65.
4.2. Analytical methods
1H, 13C, and 31P NMR (300 or 400 MHz, 75 or 100 MHz, and 121
or 162 MHz, respectively) spectra were recorded in CDCl3. Chemi-
cal shifts (d) were given relative to Me4Si (1H and 13C NMR) and
85% H3PO4 (
31P NMR) as internal standards. Spin–spin coupling
constants (J) were given in Hertz. Mass spectra were recorded with
a Finnigan SSQ 7000 (EI, 70 eV) and Thermo Deca XP (CI, 100 eV)
spectrometers. Optical rotations were measured with a Perkin–
Elmer PE-241 at 22 °C using HPLC-grade solvents. Melting points
were measured with a Büchi B-540 and were uncorrected. Analyt-
ical HPLC measurements were carried out on an Agilent 1100 chro-
matograph. Elemental analyses were performed on a Heraeus
CHNO-Rapid instrument.
4.3.5. (2S,20R,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3,1,2-
oxazaphosphabicyclo[3.3.0]-octane 5
Yield: 68% as a colorless oil. ½a D22
ꢁ
¼ þ95:8 (c 1.0, CHCl3). 1H NMR
(400 MHz, CDCl3): d 1.39–1.47 (m, 1H), 1.62–1.75 (m, 2H), 1.86–
1.92 (m, 1H), 2.99–3.08 (m, 1H), 3.14 (s, 3H), 3.28–3.38 (m, 1H),
3.83–3.89 (m, 2H), 4.49–4.53 (m, 1H), 7.59–7.62 (m, 3H), 7.94–
7.99 (m, 2H). 13C NMR (100 MHz, CDCl3): d 26.3 (d, 3J = 3.9 Hz),
31.8 (s), 47.3 (s), 49.2 (d, 2J = 34.3 Hz), 62.1 (d, 2J = 4.7 Hz), 72.4
(d, 2J = 10.4 Hz), 127.3 (s), 129.1 (s), 132.7 (s), 142.5 (s) (major epi-
mer) and 28.9 (s), 29.2 (s), 45.2 (s), 44.1 (d, 2J = 3.2 Hz), 62.9 (d,
2J = 8.7 Hz), 70.9 (d, 2J = 9.7 Hz), 127.2 (s), 128.9 (s), 132.9 (s) (min-
or epimer). HRMS: calcd m/z (C12H17N2O2PS) 284.0743; found
284.0744.
4.3. Preparation of compounds 2–9
4.3.1. General technique
A solution of the sulfoximine (3 mmol) in toluene (15 mL) was
added dropwise at ꢀ78 °C to a stirred solution of the chloro-
phosphite (3 mmol) and Et3N (0.42 mL, 3 mmol) in toluene
(15 mL). The reaction mixture was stirred at room temperature
overnight and then filtered through a short pad of neutral alumina
(ca. 3 cm, £ = 2 cm), which was washed with toluene (20 mL).
After removal of the solvent, the residue was dried in high vacuum
to give the desired product. The products are sensitive toward air
and moisture, but can be stored under cold conditions under inert
atmosphere for several months.
4.3.6. (2S,20S,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3,1,2-
oxazaphosphabicyclo[3.3.0]-octane 6
Yield: 56% as a colorless oil. ½a D22
ꢁ
¼ þ128:0 (c 1.0, CHCl3). 1H
NMR (400 MHz, CDCl3): d 1.40–1.51 (m, 1H), 1.64–1.79 (m, 2H),
1.91–1.99 (m, 1H), 3.14–3.25 (m, 1H), 3.17 (s, 3H), 3.31–3.41 (m,
1H), 3.85–3.93 (m, 2H), 4.53–4.58 (m, 1H), 7.52–7.63 (m, 3H),
4.3.2. (2R,20R,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3-
phenyl-1,3-diaza-2-phosphabicyclo[3.3.0]-octane 2
7.96–8.01 (m, 2H). 13C NMR (100 MHz, CDCl3):
d 26.5 (d,
3J = 4.0 Hz), 31.9 (s), 47.1 (s), 49.4 (d, 2J = 34.1 Hz), 62.1 (d,
2J = 4.9 Hz), 72.6 (d, 2J = 10.1 Hz), 127.6 (s), 129.1 (s), 132.9 (s),
141.7 (s) (major epimer). MS (EI, 70 eV): m/z (I, %): 284 (15), 269
(33), 202 (15), 140 (78), 130 (23), 125 (40), 83 (100), 77 (67). Anal.
Calcd for C12H17N2O2PS: C, 50.69; H, 6.03; N, 9.85. Found: C, 50.65;
H, 6.13; N, 9.99.
Yield: 78% as a colorless oil. ½a D22
ꢁ
¼ ꢀ219:2 (c 1.0, CHCl3). 1H
NMR (400 MHz, CDCl3): d 1.53–1.61 (m, 1H), 1.72–1.76 (m, 2H),
1.92–2.02 (m, 1H), 3.03 (s, 3H), 3.06–3.18 (m, 1H), 3.24–3.38 (m,
2H), 3.66–3.70 (m, 1H), 4.20–4.26 (m, 1H), 6.68 (t, 1H,
3J = 7.2 Hz), 6.94–6.96 (m, 2H), 7.16–7.20 (m, 2H), 7.34–7.38 (m,
2H), 7.44–7.47 (m, 1H), 7.77–7.80 (m, 2H). 13C NMR (100 MHz,
CDCl3):
d
26.1 (d, 3J = 5.8 Hz), 32.3 (s), 47.7 (s), 49.7 (d,
4.3.7. (2S,5S)-2-(S,S-Diphenylsulfonimidoyl)-3,1,2-
oxazaphosphabicyclo[3.3.0]-octane 7
2J = 35.0 Hz), 52.4 (d, 2J = 7.7 Hz), 63.9 (d, 2J = 8.5 Hz), 115.8 (d,
3J = 13.6 Hz), 118.1 (s), 127.1 (s), 128.7 (s), 128.8 (s), 132.3 (s),
143.0 (s), 145.6 (d, 2J = 12.2 Hz) (major epimer). HRMS: calcd m/z
359.1216 (C18H22N3OPS); found 359.1216.
Yield: 61% as a white solid; mp 63–65 °C (from toluene).
½
a 2D2
ꢁ
¼ þ57:5 (c 1.0, CHCl3). 1H NMR (400 MHz, CDCl3): d 1.40–
1.48 (m, 1H), 1.65–1.73 (m, 2H), 1.89–1.97 (m, 1H), 2.96–3.05
(m, 1H), 3.24–3.34 (m, 1H), 3.87–3.94 (m, 2H), 4.59–4.63 (m,
1H), 7.43–7.54 (m, 6H), 7.94–7.99 (m, 3H), 8.02–8.06 (m, 1H). 13C
NMR (100 MHz, CDCl3): d 26.4 (d, 3J = 3.8 Hz), 31.9 (s), 49.1 (d,
2J = 34.0 Hz), 62.2 (d, 2J = 4.8 Hz), 72.6 (d, 2J = 10.2 Hz), 127.8 (s),
128.9 (s), 132.2 (s), 132.3 (s), 142.8 (s), 143.1 (s) (major epimer).
HRMS: calcd m/z (C17H19N2O2PS+H) 347.0978; found 347.0973.
4.3.3. (2R,20S,5S)-2-(S-Methyl-S-phenylsulfonimidoyl)-3-phenyl-
1,3-diaza-2 phosphabicyclo[3.3.0]-octane 3
Yield: 86% as a white solid; mp 100–102 °C (from toluene).
½
a 2D2
ꢁ
¼ ꢀ14:4 (c 1.0, CHCl3). 1H NMR (400 MHz, CDCl3): d 1.57–
1.66 (m, 1H), 1.76–1.83 (m, 2H), 1.99–2.06 (m, 1H), 3.06 (s, 3H),
3.12–3.18 (m, 1H), 3.21–3.38 (m, 2H), 3.66–3.70 (m, 1H), 4.24–
4.27 (m, 1H), 6.77 (t, 1H, 3J = 7.2 Hz), 6.94–6.96 (m, 2H), 7.16–
7.20 (m, 2H), 7.39–7.42 (m, 2H), 7.50 (t, 1H, 3J = 7.6 Hz),
4.3.8. (2S,20S,5S)-2-(N-Benzyl-S-tert-butylsulfinamidoyl)-3,1,2-
oxazaphosphabicyclo[3.3.0]-octane 8
7.79–7.82 (m, 2H). 13C NMR (100 MHz, CDCl3):
d 26.2 (d,
Yield: 55% as a white solid; mp 110–112 °C (from toluene).
3J = 5.3 Hz), 32.3 (s), 47.1 (s), 49.9 (d, 2J = 35.4 Hz), 52.4 (d,
2J = 7.5 Hz), 63.8 (d, 2J = 8.4 Hz), 116.0 (d, 3J = 13.6 Hz), 118.3 (s),
127.4 (s), 128.8 (s), 129.0 (s), 132.5 (s), 142.3 (s), 145.8 (d,
2J = 11.9 Hz). MS (EI, 70 eV): m/z (I, %): 359 (56), 344 (100), 205
½
a 2D2
ꢁ
¼ þ234:2 (c 1.0, CHCl3). 1H NMR (300 MHz, CDCl3): d 1.19
(s, 9H), 1.31–1.39 (m, 1H), 1.63–1.84 (m, 3H), 2.72–2.83 (m, 1H),
3.29–3.51 (m, 2H), 3.57–3.64 (m, 1H), 4.26–4.38 (m, 2H), 4.53–
4.62 (m, 1H), 7.17–7.40 (m, 5H). 13C NMR (75 MHz, CDCl3): d