Synthesis of macrocyclic propargylic alcohols by ene-type cyclization of unsaturated acetylenic aldehydes
摘要:
Ene type cyclizations of ynals 6,21, and 30 can be effected by EtAlCl2 in CH2Cl2 at -78-degrees-C to afford 14-and 12-membered homoallylic propargylic alcohols in 66-89% yield.
Facile and Practical Total Syntheses of (±)-Mukulol and (±)-Cembrene by Low-valent Titanium-induced Keto Ester Cyclization
作者:Weidong Li、Ying Li、Yulin Li
DOI:10.1246/cl.1994.741
日期:1994.4
A direct approach of low-valent titanium-induced intramolecular keto ester cyclization was first applied to the total syntheses of macrocyclic diterpenoids, by which (±)-mukulol and (±)-cembrene were synthesized from geranylacetone by a short and efficient route.