12160
O. Meyer et al. / Tetrahedron 60 (2004) 12153–12162
with 86% yield. RfZ0.21 (ethyl acetate/cyclohexane, 60/
40). H NMR (300 MHz, CDCl3): dZ1.23 (3/16 of 3H, s,
(quaternary C, C-2), 208.4 (quaternary C, C-2*). IR
(CHCl3) nmax (cmK1): 1719, 1602, 1495, 1453, 1359,
1272, 1096, 1071. MS (FABC): (MCH)C 313.1. HRMS
(FABC): calcd for C19H21O4 313.1440, found 313.1437.
1
C-5), 1.25 (7/16 of 3H, s, C-5), 1.26 (5/16 of 3H, s, C-5),
1.27 (1/16 of 3H, s, C-5), 2.58 (1H, s, OH), 3.79 (5/16 of 1H,
d, J2–3Z6.6 Hz, C-3), 3.84 (1/16 of 1H, d, J2–3Z6.6 Hz,
C-3*), 3.85 (7/16 of 1H, d, J2–3Z6.6 Hz, C-3§), 3.88 (3/16
3.2.20. (3R,4S)-[5,5-2H2]-O-Benzylidene-5-O-benzylpen-
tan-2-one (13b). Colourless oil as a 1:1 mixture of two
diastereomers obtained from 12b with 86% yield. RfZ0.46
(ethyl acetate/hexane, 30/70). 1H NMR (300 MHz, CDCl3):
dZ2.30 (1/2 of 3H, s, 1-H), 2.35 (1/2 of 3H, s, 1-H*), 4.37
of 1H, d, J2–3Z6.6 Hz, C-3#), 4.23 (4/16 of 1H, d, J2–3
Z
6.6 Hz, C-2), 4.35 (5/16 of 1H, d, J2–3Z6.6 Hz, C-2*), 4.38
(7/16 of 1H, d, J2–3Z6.6 Hz, C-2§), 5.01 (3/16 of 4H, d,
JH–PZ8.2 Hz, CH2-Ph), 5.03 (5/16 of 4H, d, JH–PZ8.2 Hz,
CH2-Ph*), 5.07 (1/16 of 4H, d, JH–PZ8.2 Hz, CH2-Ph§),
5.08 (7/16 of 4H, d, JH–PZ8.2 Hz, CH2-Ph#), 5.86 (7/16 of
1H, s, CH-Ph), 5.87 (3/16 of 1H, s, CH-Ph*), 5.95 (5/16 of
1H, s, CH-Ph§), 5.96 (1/16 of 1H, s, CH-Ph#), 7.32–7.48
(15H, m, Ph). 13C NMR (75 MHz, CDCl3): dZ18.6 (CH3,
C-5, b shift: K115 ppb), 18.9 (CH3, C-5*, b shift:
K123 ppb), 19.1 (CH3, C-5§, b shift: K115 ppb), 19.8
(CH3, C-5#, b shift: K139 ppb), broad signal centred at 67.2
(CD and CD2, m, C-1 and C-4), 69.3 (CH2, d, JC–PZ5.6 Hz,
CH2-Ph), 69.5 (CH2, d, JC–PZ5.6 Hz, CH2-Ph*), 75.9 (CH,
d, JC2–PZ7.4 Hz, C-2, bCg shifts: K172 ppb), 76.2 (CH,
d, JC2–PZ7.4 Hz, C-2*, bCg shifts: K135 ppb), 77.8
(CH, d, JC2–PZ7.4 Hz, C-2§, bCg shifts: K156 ppb), 80.8
(CH, C-3, bCg shifts: K115 ppb), 81.4 (CH, C-3*, bCg
shifts: K107 ppb), 81.8 (CH, C-3§, bCg shifts: K107 ppb),
82.0 (CH, C-3#, bCg shifts: K123 ppb), 103.7 (CH,
CH-Ph), 103.9 (CH, CH-Ph*), 104.1 (CH, CH-Ph§),
126.5, 126.6, 126.7, 127.9, 128.0, 128.3, 128.4, 128.5,
128.6, 128.7, 129.4, 129.5, 129.6, 135.5, 135.6, 135.7,
136.7, 136.8 and 137.3 (aromatic C). 31P NMR (121.5 MHz,
CDCl3): dZ0.2 (s), 0.3 (s), 0.5 (s), 0.6 (s). 2H NMR
(61.4 MHz, CHCl3): dZ4.17 (s), 4.40 (s). IR (CHCl3) nmax
(cmK1): 3390, 2201, 2099, 1602, 1497, 1457, 1406, 1377,
1273, 1093, 1018. MS (FABC): (MCH)C 487.9. HRMS
(FABC): calcd for C26H27D3O7P 488.1917, found
488.1929.
(1/2 of 1H, d, J3–4Z6.5 Hz, 3-H), 4.40 (1/2 of 1H, d, J3–4
Z
6.5 Hz, 3-H*), 4.45 (1/2 of 1H, d, J3–4Z6.5 Hz, 4-H),
4.51 (1/2 of 1H, d, J3–4Z6.5 Hz, 4-H*), 4.64 (1/2 of 2H, s,
CH2-Ph), 4.65 (1/2 of 2H, s, CH2-Ph*), 5.98 (1/2 of 1H, s,
CH-Ph), 6.10 (1/2 of 1H, s, CH-Ph*), 7.31–7.56 (10H, m,
Ph). 13C NMR (75 MHz, CDCl3): dZ26.5 (CH3, C-1), 26.7
(CH3, C-1*), 69.5 (CD2, quint, JC–DZ20.2 Hz, C-5, a shift:
K501 ppb), 69.6 (CD2, quint, JC–DZ20.2 Hz, C-5*, a shift:
K546 ppb), 73.4 (CH2, 2!CH2-Ph, g shift: K131 ppb),
73.5 (CH2, 2!CH2-Ph*, g shift: K148 ppb), 78.0
(CH, C-4, b shift: K197 ppb), 78.2 (CH, C-4*, b shift:
K181 ppb), 81.9 (CH, C-3, g shift: K98 ppb), 82.2 (CH,
C-3*, g shift: K90 ppb), 105.0 (CH, CH-Ph), 126.6, 126.7,
127.5, 127.6, 127.7, 128.4, 129.6, 129.7, 136.4, 136.6 and
137.7 (aromatic C), 207.7 (quaternary C, C-2), 208.3
2
(quaternary C, C-2*). H NMR (61.4 MHz, CHCl3): dZ
3.76 (s), 3.78 (s). IR (CHCl3) nmax (cmK1): 2191, 2078,
1721, 1602, 1494, 1453, 1359, 1272, 1097, 1070. MS
(FABC): (MCH)C 315.1. HRMS (FABC): calcd for
C19H19D2O4 315.1565, found 318.1561.
3.2.21. (2R,3S)-O-Benzylidene-4-oxopentyl 1-dibenzyl-
phosphate (13c). Colourless oil as a 1:1 mixture of two
diastereomers obtained from 12c with 92% yield. RfZ0.53
1
(ethyl acetate/hexane, 8/2). H NMR (300 MHz, CDCl3):
dZ2.26 (1/2 of 3H, s, 5-H), 2.30 (1/2 of 3H, s, 5-H*), 4.26
(3H, m, 1-, 2- and 3-H), 5.03 (1/2 of 4H, d, JH–PZ8.4 Hz,
CH2-Ph), 5.08 (1/2 of 2H, d, JH–PZ8.4 Hz, CH2-Ph*), 5.09
(1/2 of 2H, d, JH–PZ8.4 Hz CH2-Ph*), 5.90 (1/2 of 1H, s,
CH-Ph), 5.97 (1/2 of 1H, s, CH-Ph*), 7.32–7.50 (15H, m,
Ph). 13C NMR (75 MHz, CDCl3): dZ26.6 (CH3, C-5), 26.7
(CH3, C-5*), 66.6 (CH2, d, JC1–PZ5.6 Hz, C-1), 66.9 (CH2,
d, JC1–PZ5.6 Hz, C-1*), 69.4 (CH2, d, JC–PZ5.6 Hz,
CH2-Ph), 69.5 (CH2, d, JC–PZ5.6 Hz, CH2-Ph*), 76.8
(CH, d, JC2–PZ8.0 Hz, C-2), 76.9 (CH, d, JC2–PZ7.4 Hz,
C-2*), 81.4 (CH, C-3), 81.6 (CH, C-3*), 105.0 (CH,
CH-Ph), 105.1 (CH, CH-Ph*), 126.6, 126.7, 127.9, 128.0,
128.4, 128.5, 128.6, 129.7, 129.8, 135.5, 135.6, 135.9 and
136.2 (aromatic C), 206.8 (quaternary C, C-4), 207.7
(quaternary C, C-4*). 31P NMR (121.5 MHz, CDCl3): dZ
0.2 (s), 0.3 (s). IR (CHCl3) nmax (cmK1): 1722, 1602, 1497,
1455, 1406, 1380, 1269, 1090, 1017. MS (FABC): (MC
H)C 483.1. HRMS (FABC): calcd for C26H28O7P
483.1573, found 483.1573.
3.2.18. General procedure for oxidation. To a solution of
the alcohol (1 equiv) in dichloromethane (2 mL/mmol) were
˚
added activated 4 A molecular sieves, N-methylmorpholin-
N-oxide (3.5 equiv) and solid TPAP (0.1 equiv). The
mixture was stirred at room temperature and monitored by
TLC until the starting material completely disappeared. The
reaction mixture was then filtered through a layer of silica
on a sintered-glass funnel. The solid cake was washed with
ethyl acetate, and the filtrate was evaporated. The residue
was purified by flash chromatography.
3.2.19. (3R,4S)-O-Benzylidene-5-O-benzylpentan-2-one
(13a). Colourless oil as a 1:1 mixture of two diastereomers
obtained from 12a with 86% yield. RfZ0.43 (ethyl acetate/
cyclohexane, 30/70). 1H NMR (300 MHz, CDCl3): dZ2.29
(1/2 of 3H, s, 1-H), 2.34 (1/2 of 3H, s, 1-H*), 3.78 (2H, m,
5-H), 4.37 (1H, m, 4-H), 4.43 (1/2 of 1H, d, J3–4Z6 Hz,
3-H), 4.50 (1/2 of 1H, d, J3–4Z6 Hz, 3-H*), 4.63 (1/2 of 2H,
s, CH2-Ph), 4.64 (1/2 of 2H, s, CH2-Ph*), 5.96 (1/2 of 1H, s,
CH-Ph), 6.09 (1/2 of 1H, s, CH-Ph*), 7.29–7.54 (10H, m,
Ph). 13C NMR (75 MHz, CDCl3): dZ26.5 (CH3, C-1), 26.8
(CH3, C-1*), 70.0 (CH2, C-5), 70.4 (CH2, C-5*), 73.5 (CH2,
2!CH2-Ph), 73.6 (CH2, 2!CH2-Ph*), 78.2 (CH, C-4),
78.3 (CH, C-4*), 82.1 (CH, C-3), 82.3 (CH, C-3*), 105.1
(CH, CH-Ph), 126.7, 126.8, 127.6, 127.7, 127.8, 128.4,
129.6, 129.7, 136.4, 136.6 and 137.7 (aromatic C), 207.8
3.2.22. (2R,3S)-[5,5-2H2]-O-Benzylidene-4-oxopentyl 1-di-
benzylphosphate (13d). Colourless oil as a 1:1 mixture of
two diastereomers obtained from 12d with 93% yield. RfZ
0.38 (ethyl acetate/hexane, 60/40). 1H NMR (300 MHz,
CDCl3): dZ2.26 (1/2 of 3H, s, 5-H), 2.30 (1/2 of 3H, s,
5-H*), 4.35 (2H, m, 2- and 3-H), 5.04 (1/2 of 4H, d, JH–P
Z
8.4 Hz, CH2-Ph), 5.08 (1/2 of 2H, d, JH–PZ8.4 Hz, CH2-
Ph*), 5.09 (1/2 of 2H, d, JH–PZ8.4 Hz, CH2-Ph*), 5.90 (1/2