Chiral terpene auxiliaries V: Synthesis of new chiral γ-hydroxyphosphine oxides derived from α-pinene
作者:Anna Kmieciak、Marek P Krzemiński
DOI:10.3762/bjoc.15.242
日期:——
New chiral regioisomeric γ-hydroxyphosphine ligands were synthesized from α-pinene. The key transformation was the thermal [2,3]-sigmatropic rearrangement of allyldiphenylphosphinites, obtained from (1R,2R,4S,5R)-3-methyleneneoisoverbanol and (1R,2R,3R,5R)-4-methyleneneoisopinocampheol, to allylphosphine oxides. Hydroxy groups were introduced stereoselectively through a hydroboration–oxidation reaction
Synthesis of racemic and optically active .DELTA.9-tetrahydrocannabinol (THC) metabolites
作者:Craig Siegel、Patrick M. Gordon、David B. Uliss、G. Richard Handrick、Haldean C. Dalzell、Raj. K. Razdan
DOI:10.1021/jo00024a031
日期:1991.11
The preparation of racemic and optically active DELTA-9-THC metabolites is described from synthon 13. Racemic synthon 13 is prepared in four steps (46%) from Danishefsky's diene. Optically active synthon 13 is prepared from perillaldehyde via the enone 22 in six steps (23% yield). Alternatively, nopinone can be converted to 13 in three steps (50% yield) via a cyclobutane ring cleavage. The acid-catalyzed condensation of 13 with olivetol (6a) and subsequent conversion to 11-hydroxy and 9-carboxyl DELTA-9-THC metabolites 2a and 4a is described, as well as the preparation of 1',1'-dimethylheptyl THC analogues 2b, 3b, and 4b from 5-(1',1'-dimethylheptyl)resorcinol (6c).