Synthesis of a Butyrolactone Precursor of an Algae Nonaether from an Enantiopure Glycol Obtained by Hoppe's Chemistry
摘要:
Homoallyl carbamate 20, (-)-sparteine, and sBuLi gave a lithium derivative which was formylated with DMF giving the crude aldehydocarbamate 19. With Lithium aluminum hydride in refluxing THF, this compound provided diol 22 in 90% overall yield and with 96% ee. This material was carried on to the gamma-lactone monoethers 13 (benzyl ether) or 14 (trityl ether). These compounds should be precursors for synthesizing the naturally occurring nonaether 7.
Synthesis of a Butyrolactone Precursor of an Algae Nonaether from an Enantiopure Glycol Obtained by Hoppe's Chemistry
摘要:
Homoallyl carbamate 20, (-)-sparteine, and sBuLi gave a lithium derivative which was formylated with DMF giving the crude aldehydocarbamate 19. With Lithium aluminum hydride in refluxing THF, this compound provided diol 22 in 90% overall yield and with 96% ee. This material was carried on to the gamma-lactone monoethers 13 (benzyl ether) or 14 (trityl ether). These compounds should be precursors for synthesizing the naturally occurring nonaether 7.
All-carbon quaternary stereocenters: A zirconium-catalyzed double carboalumination of various unactivated 1,5-dienes provides efficient access to chiral cyclopentanes with two stereocenters, including one all-carbon quaternary stereocenter, through the formation of two new C−C bonds as well as one C−Al bond with high diastereo- and enantioselectivity.
Homoallyl carbamate 20, (-)-sparteine, and sBuLi gave a lithium derivative which was formylated with DMF giving the crude aldehydocarbamate 19. With Lithium aluminum hydride in refluxing THF, this compound provided diol 22 in 90% overall yield and with 96% ee. This material was carried on to the gamma-lactone monoethers 13 (benzyl ether) or 14 (trityl ether). These compounds should be precursors for synthesizing the naturally occurring nonaether 7.