Well‐Defined, Versatile and Recyclable Half‐Sandwich Nickelacarborane Catalyst for Selective Carbene‐Transfer Reactions
作者:Linghua Wang、Saima Perveen、Yizhao Ouyang、Shuai Zhang、Jiao Jiao、Gang He、Yong Nie、Pengfei Li
DOI:10.1002/chem.202005014
日期:2021.3.26
accessible nickel(II)‐based complexes have been rarely used. Herein, an air‐stable nickel(II)‐carborane complex is reported as a well‐defined, versatile and recyclable catalyst for selective carbene transfer reactions with low catalyst loading undermildconditions. This catalyst is effective for several types of reactions including diastereoselective cyclopropanation, epoxidation, selective X−H insertions
Stereoselective Insertion of Rhodium Carbenoid to Water under Control with Intramolecular Participation of Hydroxy Group
作者:Takashi Sugimura、Takao Nagai
DOI:10.1246/cl.2008.286
日期:2008.3.5
A chiral diazo ester having a hydroxy group in the proper geometry produces an adduct with water up to 92% de upon treatment with a rhodium catalyst. This high stereoselectivity is attributable to the intramolecular hydrogen bond between the internal hydroxy group and the rhodium carbenoid.
New chiral rhodium(II) carboxylates and their use as catalysts in carbenoid transformations
作者:Leigh Ferris、David Haigh、Christopher J. Moody
DOI:10.1016/0040-4039(95)02085-3
日期:1996.1
Newchiral dirhodium(II) carboxylates 11–15 have been prepared from the half phthalate esters 6–8 and the pyrroles 9 and 10, and their use as catalysts for the decomposition of diazocarbonyl compounds 16 and 18 investigated.
Water Compatible Gold(III)-Catalysed Synthesis of Unsymmetrical Ethers from Alcohols
作者:Ana B. Cuenca、Gisela Mancha、Gregorio Asensio、Mercedes Medio-Simón
DOI:10.1002/chem.200701134
日期:2008.2.8
preparation of unsymmetricalethersfromalcohols catalysed by the simplest and least expensive gold catalyst, NaAuCl(4), is described for the first time. The procedure enables the etherification of benzylic and tertiary alcohols with moderate to good yields under mild conditions with low catalyst loading. Symmetrical ethers, the usual side products in the etherification of alcohols, were not detected
The first effective method for catalytic enantioselective insertions into O-H bonds has been developed. Specifically, a copper/bisazaferrocene catalyst couples alcohols such as 2-trimethylsilylethanol with alpha-aryl-alpha-diazo esters in high yield and good ee.