162085-16-7Relevant academic research and scientific papers
Catalytic diastereoselective polycyclization of homo(polyprenyl)arene analogues bearing terminal siloxyvinyl groups
Uyanik, Muhammet,Ishihara, Kazuaki,Yamamoto, Hisashi
, p. 5649 - 5652 (2007/10/03)
Highly diastereoselective polycyclization of homo(polyprenyl)arene analogues bearing terminal siloxyvinyl groups was catalyzed by tin(IV) chloride (10 mol %). The cyclizations of tert-butyldiphenylsilyl and triisopropylsilyl polyenol ethers gave 4α(equatorial)- and 4β(axial)-siloxypolycycles as major isomers, respectively. The strong nucleophilicity of pro-C(9), a (6E) geometry, and a bulky silyl group effectively favored the 4α-preference, whereas the weak nucleophilicity of pro-C(9), a (6Z)-geometry, and less steric hindrance of a silyl group favored the 4β-preference.
Tandem carbonyl ene cyclization-cycloalkylation: A route to trifluoromethyl diterpenoids
Abouabdellah, Ahmed,Bonnet-Delpon, Daniele
, p. 11921 - 11932 (2007/10/02)
A new sequential carbonyl-ene cyclization/cycloalkylation of trifluoromethyl ketones catalyzed by aluminum Lewis acids is described. From ketone 1, the 4-CF3-4-OH cis-octahydrophenanthrene 6 is obtained in 50% yield. From ketone 2, with MeAlCl
