Stereoselective synthesis of 1α-hydroxyvitamin D3 A-ring synthons by palladium-catalyzed cyclization
摘要:
Palladium-catalyzed cyclization of 8-bromo-2,8-nonadienoates proceeded stereoselectively to give 1-alpha-hydroxyvitamin D3 A-ring synthons in good yields.
DOI:
10.1016/s0040-4039(00)93501-9
作为产物:
描述:
2-溴丙烯醛 、 dianion of methyl acetoacetate 以75%的产率得到Methyl 6-Bromo-5-hydroxy-3-oxo-6-heptenoate
参考文献:
名称:
Stereoselective synthesis of 1α-hydroxyvitamin D3 A-ring synthons by palladium-catalyzed cyclization
摘要:
Palladium-catalyzed cyclization of 8-bromo-2,8-nonadienoates proceeded stereoselectively to give 1-alpha-hydroxyvitamin D3 A-ring synthons in good yields.
Chiral synthesis of the A-ring synthon 3 of 1alpha,25-dihydroxyvitamin D3 (1a) based on palladium-catalyzed cyclization of 8-bromo-2,8-nonadienoates is described. Reaction of (E)-4b and (Z)-4d in the presence of Pd(OAc)2, PPh3, and K2CO3 gave (E)-3b and (Z)-3d, respectively. Optically active 4d was prepared from 24 by asymmetric aldol reaction using 31, which was cyclized to 3d. With further reactions, 1alpha,25-dihydroxyvitamin D3 (1a) was obtained.
JPH04305548A
申请人:——
公开号:JPH04305548A
公开(公告)日:1992-10-28
Stereoselective synthesis of 1α-hydroxyvitamin D3 A-ring synthons by palladium-catalyzed cyclization
Palladium-catalyzed cyclization of 8-bromo-2,8-nonadienoates proceeded stereoselectively to give 1-alpha-hydroxyvitamin D3 A-ring synthons in good yields.