Terminal allylicalcohols are important motifs in natural products, and also key intermediates/precursors in numerous novel reaction transformations. In this study, enabled by a bifunctional ligand featuring a basic amino group, a gold-catalyzed hydroarylation of terminal unactivated propargylic alcohols with heteroareneboronic acids has been first established, and efficiently affords various terminal
Regioselective Ni-Catalyzed Carboxylation of Allylic and Propargylic Alcohols with Carbon Dioxide
作者:Yue-Gang Chen、Bin Shuai、Cong Ma、Xiu-Jie Zhang、Ping Fang、Tian-Sheng Mei
DOI:10.1021/acs.orglett.7b01208
日期:2017.6.2
efficient Ni-catalyzed reductive carboxylation of allylic alcohols with CO2 has been successfully developed, providing linear β,γ-unsaturated carboxylic acids as the sole regioisomer with generally high E/Z stereoselectivity. In addition, the carboxylic acids can be generated from propargylicalcohols via hydrogenation to give allylic alcohol intermediates, followed by carboxylation. A preliminary mechanistic
Asymmetric Synthesis of Ramariolides A and C through Bimetallic Cascade Cyclization and <i>Z</i>–<i>E</i> Isomerization Reaction
作者:Pratik Pal、Samik Nanda
DOI:10.1021/acs.orglett.7b00202
日期:2017.3.3
A short and flexible asymmetric synthesis of ramariolides A and C was accomplished. A bimetallic catalytic system consisting of Pd–Cu-mediated cascade cyclization, unprecedented Z–E isomerization by a Ru-based metathesis catalyst, and late-stage stereoselective epoxidation are the key steps involved in the synthesis.
Primary alcohols undergo selective and efficient tetrahydropyranylation in the presence of a catalytic amount of La(NO3)3·6H2O undersolvent-freeconditions.
Synthesis of the Pseudopterane and Furanocembrane Ring Systems by Intraannular Cyclization of .beta.- and .gamma.-Alkynyl Allylic Alcohols
作者:James A. Marshall、William J. DuBay
DOI:10.1021/jo00086a018
日期:1994.4
The prototype pseudopterane and furanocembrane systems 15 and 26 were prepared through a ''furan last'' approach. The former was obtained in 64% yield upon treatment of the 12-membered beta-alkynyl allylic alcohol 14 with KO-t-Bu and 18-c-6 in THF-t-BuOH. The latter was formed in 88% yield from the 14-membered gamma-alkynyl allylic alcohol 25 under comparable conditions. The carbocyclic precursors to these allylic alcohols, 11 and 24, were secured through intramolecular Horner-Emmons condensation of keto phosphonates 10 and 23, respectively, under Masamune-Roush conditions.