Alkynes as Allylmetal Equivalents in Redox-Triggered C–C Couplings to Primary Alcohols: (<i>Z</i>)-Homoallylic Alcohols via Ruthenium-Catalyzed Propargyl C–H Oxidative Addition
作者:Boyoung Y. Park、Khoa D. Nguyen、Mani Raj Chaulagain、Venukrishnan Komanduri、Michael J. Krische
DOI:10.1021/ja505962w
日期:2014.8.27
The cationic ruthenium catalyst generated upon the acid–base reaction of H2Ru(CO)(PPh3)3 and 2,4,6-(2-Pr)3PhSO3H promotes the redox-triggered C–C coupling of 2-alkynes and primaryalcohols to form (Z)-homoallylic alcohols with good to complete control of olefin geometry. Deuterium labeling studies, which reveal roughly equal isotopic compositions at the allylic and distal vinylic positions, along with
[reaction: see text] Electrochemical arylation of arenecarboxaldehydes using an iron sacrificial anode in the presence of chromium and nickel catalysts afforded the corresponding arylated secondary alcohols in moderate to good yields. The chromium and nickel salts as catalysts are obtained by oxidation of a stainless steel rod during a preelectrolysis in 7% and 3%, respectively. The process was also
Palladium-catalyzed enantioselective Heck alkenylation of trisubstituted allylic alkenols: a redox-relay strategy to construct vicinal stereocenters
作者:Chun Zhang、Brandon Tutkowski、Ryan J. DeLuca、Leo A. Joyce、Olaf Wiest、Matthew S. Sigman
DOI:10.1039/c6sc04585e
日期:——
An enantioselective, redox-relay Heck alkenylation of trisubstituted allylic alkenol substrates has been developed. This process enables the construction of vicinal stereocenters in high diastereo- and enantioselectivity and allows the formation of enolizable α-carbonyl methyl-substituted stereocenters with no observed epimerization under the reported reaction conditions.
Rhodium-Catalyzed Synthesis of γ-Pyrones by Three Consecutive Redox-Aldol Reactions of Allylic Alcohols with α,β-Unsaturated Aldehydes
作者:Akio Mizuno、Hiroyuki Kusama、Nobuharu Iwasawa
DOI:10.1002/chem.201001068
日期:——
All together now! A unique RhI‐catalyzed reaction was developed to produce γ‐pyrones, which are 1,3,5‐triketone equivalents. This reaction was thought to proceed by three redox reactions of allylicalcohols, two intermolecular aldol reactions of α,β‐unsaturated aldehydes, and one intramolecular aldol reaction to afford 1,3‐cyclohexanediones, which were then converted into γ‐pyrones (see scheme; TMSOTf=trimethylsilyl
Vinyllithiums from butyl-vinyl tellurides and bis-vinyl tellurides
作者:Simone M. Barros、João V. Comasseto、Jorge Berriel
DOI:10.1016/s0040-4039(00)70695-2
日期:1989.1
Butyl vinyl tellurides and bis-vinyl tellurides furnish vinyllithiums with retention of configuration in good yields upon treatment with n-butyllithium at −78°C.