(Trimethylstannyl)vinyl Cuprates: Generation and Conjugate Addition Reactions
摘要:
A new convenient route to the bis[(trimethylstannyl)vinyl] cuprate reagent 9 is described. Its addition to alpha,beta-unsaturated ketones has been studied, Bis(trimethylsilyl)acetamide (BSA) was found to activate 1,4-conjugate addition of 9 to alpha,beta-unsaturated ketone esters without concomitant reduction of the double bond.
Photoredox/Cobalt Dual Catalysis for Visible-Light-Mediated Alkene–Alkyne Coupling
作者:Pramod Rai、Kakoli Maji、Biplab Maji
DOI:10.1021/acs.orglett.9b01201
日期:2019.5.17
Dual photoredox transition-metal catalysis has recently emerged as a powerful tool for making synthetically challenging carbon–carbon bonds under milder reaction conditions. Herein, we report on the visible-light-mediated controlled generation of low-valent cobalt catalyst without the need for a metallic reductant. It enabled C–C bondformation via ene-yne coupling at roomtemperature. The generality
Palladium-catalyzed anti-Markovnikov oxidative acetalization of activated olefins with iron(<scp>iii</scp>) sulphate as the reoxidant
作者:Rodney A. Fernandes、Sandhya S. Yadav、Praveen Kumar
DOI:10.1039/d1ob02227j
日期:——
efficient palladium-catalyzed anti-Markovnikov oxidative acetalization of activated terminal olefins with iron(III) sulfate as the reoxidant. This methodology requires mild reaction conditions and shows high regioselectivity toward anti-Markovnikov products and compatibility with a wide range of functional groups. Iron(III) sulphate was the sole reoxidant used in this method. Various olefins like vinylarenes
本文公开了以硫酸铁( III )为再氧化剂的活性末端烯烃的高效钯催化抗马尔科夫尼科夫氧化缩醛化反应。该方法需要温和的反应条件,并显示出对抗马尔科夫尼科夫产物的高区域选择性以及与多种官能团的相容性。硫酸铁( III ) 是该方法中使用的唯一再氧化剂。各种烯烃,如乙烯基芳烃、芳基烯丙基醚、丙烯酸芳基或苄基丙烯酸酯和高烯丙醇都反应良好,提供抗马尔科夫尼科夫缩醛,其中一些代表正交官能化的 1,3-和 1,4-二氧化化合物。
Asymmetric Michael addition of malonic diesters to acrylates by phase-transfer catalysis toward the construction of quaternary stereogenic α-carbons
A highlyenantioselective construction of an all-carbon quaternary stereogenic center at the α-position of malonic diesters has been achieved by Michaeladditionusing phase-transfer catalysis. The reaction of α-monosubstituted malonates with acrylates in the presence of N-(9-anthracenylmethyl)quininium chloride as a phase-transfer catalyst afforded the corresponding α,α-disubstituted malonic diesters
An efficient Co-catalyzed 1,4-addition reaction of alkyl/aryl triflates and tosylates with activated alkenes is described. In this reaction, air-stable cobalt(II) complex, mild reducing agent Zn and simple proton source (H2O) are used. A radical mechanism for the addition of alkyl tosylates to activated alkenes is likely involved.