A Novel Approach to Bicyclic Alkaloids Using a Tandem Diastereoselective Acyliminocyclization and Retro Diels–Alder Reaction Sequence. Synthesis of (+)-Indolizidine and (+)-Laburnine
作者:Yoshitsugu Arai、Tohru Kontani、Toru Koizumi
DOI:10.1246/cl.1991.2135
日期:1991.12
A new approach to a diastereoselective cationic cyclization by stereocontrol due to the bicyclo[2.2.1]heptene moiety in a chiral γ-hydroxy lactam is described. The diastereoselective reaction followed by Diels–Alder cycloreversion has been successfully applied to a chiral synthesis of (+)-indolizidine and (+)-laburnine (=trachelanthamidine).
Chemistry of Novel Compounds with Multifunctional Carbon Structure. 8. Application of the α-Cyano-α-fluorophenylacetic Acid (CFPA) Method to the Enantiomeric Excess Determination of Some Hindered Alcohols in Asymmetric and Natural Product Syntheses
pinacolyl alcohol was found to proceed more than 500 times faster than that of MTPA chloride (1b) suggesting that the CFPA method induces potentially much less kinetic resolution than the widely used MTPA method in enantiomeric excess (ee) determination. Some applications of CFPA method were also investigated to evaluate practical use of CFPA reagent in ee determination of some hindered alcohols in asymmetric