J. Org. Chem. 1989,54,5539-5543 till all the diethylammonium trichloromethanesulfonate salt precipitated, while the azaphosphetine cation 3d remained in solution. Evaporation of the solution afforded 3d as a brown oil. 3d: yield 50%. 31PNMR (CDCQ: 6 132.4 ppm. 'H NMR (CDCl3): 6 1.00 (t,3 J = ~7 HZ, ~ 3 H, CH&H,), 1.12 (t,3J" = 7 Hz, 9 H, CHaCH,), 1.15 [s,9 H, C(CH3)3], 1.33 [s, 9 H, C(CH&3], 2.6-2.9 (m, 8 H, CH2CH3)ppm. 13C NMR (CDC13): 6 11.34 [s, CN(CH,CH3),I, 14.0 [s, CN(CH,CH,),I, 14.2 [m, PN(CHZCH3),, 30.2 [d, 4Jcp = 4.6 Hz,NC(CH3)2], 31.3 [d, 4Jcp = 6.4 Hz, = NC(CH3)3],41.9 [d, 2Jcp= 13.1 Hz, PN(CHZCH,),], 43.4 [s, CN(CH&HS)z, 46.9 [s, CN(CH,CH,),], 45.8 [d, 'Jcp = 45 Hz, PN (CHZCH,),], 58.65 [d, ,Jcp = 6.4 Hz, >NC(CH,),], 63.58 [d, ,Jcp = 1 Hz, =NC(CHJJ, 120.83 (4,'JCF = 319.7 Hz, CF,SO 201): [ a I m D = -3.7O (c 0.92, CHCl,); 'H NMR 6 CHC13). The 'H NMR spectrum of 29/30 was identical with the spectrum of 25/26. Anal. Calcd for C'OH2807:C, 63.14; H, 7.42. 4.28, 4.02 (d AB q, each 1 H, JAB= 11.7 Hz, J1,2, J1t,2 = 1.9, 5.0 Hz, H-1, H-l'), 3.88 (m, 1 H, J2,3 = 9.3 Hz, H-2), 3.81 (dd, 1 H, Found: C, 63.02; H, 7.44. (2S,3S ,4S ,5R / S)-5-0-Benzyl-4-methyl-7-(trimethyl- 5 3 4 = 4.2 Hz, H-3), 3.16 (4, 1H, 55,s = 6.5 Hz, H-5), 2.07 (5, 3 H, silyl)-2-0-(tert -butyldimethylsilyl)hept-6-yne-1,2,3,5-tetrol CbMe), 1.79 (m, 1 H, J4,5 = 6.9 Hz, H-4), 1.50 (m, 2 H, H-6), 1.30, 1.30 (2 s, each 3 H, Me&), 0.94 (d, 3 H, JMe,4 (31/32). Compound 8 (94 mg, 267 pmol) was subjected to reaction = 6.8 Hz, 4-Me), 0.87 (s,9 H, Me,CSi), 0.70, 0.41 (AB q complex, each 1H, H-7), conditions B1 (50 "C, 1 h). Column chromatography (E/H, 1:7) 0.10,0.08 (2 s, each 3 H, Me&), 0.00 (s,9 H, Me3Si). Anal. Calcd gave 31/32 (syrup, 80.3 mg, 67%, diastereomeric ratio 1:4 defor Cz2H6O5Si2:C, 59.14; H, 10.38. Found: C, 59.08; H, 10.70. termined by GC after acetylation). The major diastereomer had the following: [a12'D = +82.6' (e 1.06, CHC13). The minor diaAcknowledgment. We t h a n k The Swedish Natural stereomer had the following: [a]'OD = -61.9' (c 0.64, CHC13). The Science Research Council and T h e Swedish Board for IR and 'H NMR spectra of the two diastereomers 31 and 32 were Technical Development for financial support and Maria identical with the spectra of 27 and 28. Anal. Calcd for C24H4204Si2: C, 63.95; H, 9.39. Found: C, 63.79; H, 9.51. Levin and Rolf Servin for skillful technical assistance. Benzyl 3-Deoxy-3-C-methyl-4-O-(tert-butyldimethyl- Registry No. 5,115983-63-6;6,115983-66-9; 6 (3-OTBSderiv), silyl)-&D-arabinopyranoside (33) a n d (25,35,45,5R/S)122822-31-5;7,115983-65-8;8, 115983-68-1; 10,115983-67-0;11, 1,4-Di-0 -acetyl-5-0-benzyl-3-methyl-2-O -(tert -butyldi115983-64-7; 13, 122921-07-7;13 (1-0-acetate),122822-27-9;13 methylsilyl)-1,2,4,5-hexanetetrol(34/35). Benzyl 3-deoxy-3(1-0-acetate 5-0-debenzyl deriv), 122822-28-0; 13 (diacetate), C-methyl-4-0-(tert-butyldimethylsilyl)-a-~arabmopyranceide (11) 122822-18-8;14, 122822-17-7;14 (1-0-acetate),122920-25-6; 14 (64mg, 182 pmol) was subjected to reaction conditions A (reflux, (1-0-acetate 5-0-debenzyl deriv), 122920-26-7; 14 (diacetate), 18 h). Column chromatography (E/H, 1:6) gave 33 (44.4 mg, 69%) 122920-09-6;15, 122822-19-9;16, 122920-10-9;17, 122920-11-0; and a ring-opened diol, which was difficult to purify and therefore 17 (diacetate), 122920-12-1; 18, 122822-20-2; 18 (diacetate), was acetylated. Column chromatography (E/H, 1:3) gave the 122920-13-2; 19, 122920-14-3;20, 122920-15-4;21, 122822-21-3; diacetate 34/35 (22.1 mg, 27%, diastereomeric ratio >25:1). 33: 22,122920-16-5; 23,122822-22-4; 24,122920-17-6; 25,122822-23-5; = -160' (c 1.03, CHC1,). The 'H NMR spectrum of 33 was 26,122920-18-7; 27,122920-19-8; 28,122920-20-1; 29,122822-24-6; identical with the spectrum of compound 12 (enantiomer) (cf. ref 30,122920-21-2;31,122920-22-3; 32,122920-23-4; 33,122822-25-7; 2, compound 21). Anal. Calcd for C19H3204Si:C, 64.73; H, 9.15. 34,122822-26-8;35,122920-24-5; 36,122822-29-1; 37,122920-27-8; Found: C, 64.75; H, 9.20. 38, 122822-30-4;39, 122998-80-5;B1,66530-05-0;B2,77102-19-3; 34/35: [ C Y ] ~ = D -20.7' ( C 0.96, CHCl3); 'H NMR 6 7.32 (m, 5 B3, 122822-16-6;Me3A1, 75-24-1. H, CsH6),5.14 (dd, 1H, J3,4= 4.3 Hz, H-3), 4.58,4.51 (AB q, each 1 H, JAB = 11.7 Hz, CH2Ph),4.10,3.98 (d, AB q, each 1 H, JAB Supplementary Material Available: Discussion about the = 11.4 Hz, J1,2, J1,,2 = 3.7, 6.9 Hz, H-1, H-l'), 3.78 (m, 1 H, J2,3 structure determination of 36/37 and 38/39; Scheme IV and Figure 1showing the calculated (MM2(85))low-energy conformers = 4.8 Hz, H-2), 3.66 (dq, 1 H, 54,5 = 5.2 Hz, H-5), 2.14 (m, 1 H, H-4), 2.06, 2.02 (s, each 3 H, COMe), 1.18 (d, 3 H, J5,s = 6.4 Hz, of model acetonides 36'-39'; Table 2 listing calculated (3JHH) H-6), 0.96 (d, 3 H, JMS,, = 7.1 Hz, 3-Me), 0.88 (s, 9 H, Me3CSi), and experimental NMR coupling constant data for 36'-39', 36, 0.06 (s, 6 H, Me2Si). Anal. Calcd for C24H4008Si:C, 63.68; H, and 38; Figure 2 showing selected NOE data for acetonides 36 8.91. Found: C, 63.51; H, 9.01. and 38; Experimental Section describing the preparation of 6(3OTBS) (4 pages). Ordering information is given on any current (2S,3R,4S,5R)- and (2R,3R,4S,5S)-l-O-Acety1-3,5-di-Omasthead page. isopropylidene-4-methyl-20 -( tert -butyldimethylsilyl)-
