The use of a malonate nucleophile in the transition metal-catalyzed hydroalkylation of 1,3-dienes remains immature. Herein, we report the nickel-catalyzed hydroalkylation of 1,3-dienes with malonates using a homoallylcarbonate as the 1,3-diene and hydridesource. A broad range of homoally carbonates and malonate derivatives were well tolerated under a Ni/DPEphos catalyst system, providing the corresponding
Nickel-Catalyzed Hydroarylation of in Situ Generated 1,3-Dienes with Arylboronic Acids Using a Secondary Homoallyl Carbonate as a Surrogate for the 1,3-Diene and Hydride Source
The nickel-catalyzedhydroarylation of 1,3-dienes with arylboronicacidsusing a secondaryhomoallylcarbonate as a surrogate for the 1,3-diene and hydridesource has been developed. The synthetic strategy allowed an efficient access to a wide array of hydroarylation products in high yields with high functional group compatibility without the use of an external hydridesource. Mechanistic experiments
TBD catalysis with dimethyl carbonate: a fruitful and sustainable alliance
作者:Hatice Mutlu、Johal Ruiz、Susanne C. Solleder、Michael A. R. Meier
DOI:10.1039/c2gc35191a
日期:——
This work presents the synthesis of unsymmetric and symmetric organic carbonates as well as the synthesis of polycarbonates in an efficient and sustainable approach. All reactions were carried out at atmospheric pressure at 80 °C and the use of classic toxic and harmful chemicals, such as phosgene and carbon monoxide, was avoided. The key finding of this manuscript is that the use of 1,5,7-triazabicyclo[4.4.0]dec-5-ene, TBD, an organocatalyst, in combination with dimethyl carbonate (DMC), a non-toxic and renewable starting material, allows the synthesis of the mentioned unsymmetric carbonates in yields of up to 98% under optimized conditions. The structure of the alcohols used for this approach was found to influence the DMC–ROH ratio required to maximize the yield of the desired structure. Finally, the results obtained for the synthesis of low molecular weight building blocks could be transferred to the catalytic synthesis of high molecular weight polycarbonates.
这项研究以高效、可持续的方法合成了不对称和对称有机碳酸盐以及聚碳酸酯。所有反应都是在 80 °C 的常压下进行的,避免了使用传统的有毒有害化学品,如光气和一氧化碳。本手稿的主要发现是,使用 1,5,7-三氮杂双环[4.4.0]癸-5-烯(TBD,一种有机催化剂)与碳酸二甲酯(DMC,一种无毒且可再生的起始原料)相结合,可以在优化的条件下合成上述不对称碳酸盐,产率高达 98%。研究发现,这种方法所使用的醇的结构会影响 DMC-ROH 的比例,从而使所需结构的产率最大化。最后,合成低分子量结构单元的结果可用于催化合成高分子量聚碳酸酯。
Nickel-catalyzed Markovnikov 1,2-Hydroboration of In Situ Generated 1,3-Dienes Using a Secondary Homoallylic Carbonate as the 1,3-Diene and Hydride Source
regioselective hydroboration of 1,3-dienes has been received continuous interests in the field of organic synthesis. Herein, we describe the nickel-catalyzed Markovnikov 1,2-hydroboration of in situgenerated1,3-dienes with bis(pinacolato)diboron using a secondary homoallyic carbonate as the 1,3-diene and hydridesource. The catalytic hydroboration of in situgenerated1,3-dienes proceeded in the presence
过渡金属催化的1,3-二烯的区域选择性硼氢化反应在有机合成领域一直受到关注。本文中,我们描述了使用仲均碳酸酯作为1,3-二烯和氢化物源,用双(频哪醇)二硼原位生成的1,3-二烯进行镍催化的Markovnikov 1,2-氢硼化反应。在存在Ni(cod)2 / P(p -MeOC 6 H 4)3作为催化剂的情况下,原位生成的1,3-二烯催化加氢硼化反应以42-77%的收率得到相应的仲烯丙基硼酸酯,高选择性(12个例子)。
Anodic oxidation of α-alkoxycarbonyloxy and α-acyloxy organotin compounds
Electrochemical behavior of alpha-alkoxycarbonyloxy and alpha-acyloxy organotin compounds was studied. Preparative anodic oxidation in the presence of allylsilanes or silyl enol ethers gave the corresponding coupling products.