DDQ-Catalyzed Oxidative CO Coupling Of sp<sup>3</sup>CH Bonds With Carboxylic Acids
作者:Hong Yi、Qiang Liu、Jie Liu、Ziqi Zeng、Yuhong Yang、Aiwen Lei
DOI:10.1002/cssc.201200458
日期:2012.11
catalytic amounts of DDQ combined with MnO2 as oxidant, an efficient oxidative CO coupling of benzylic sp3 CH bonds with carboxylic acids affords a series of carboxylic esters in 70–98 % yields. A wide range of functional groups and various carboxylic acids are tolerated. The reaction involves both CH functionalization and CO bond formation.
Sulfonated nanohydroxyapatite functionalized with 2-aminoethyl dihydrogen phosphate (HAP@AEPH2-SO3H) as a reusable solid acid for direct esterification of carboxylic acids with alcohols
catalyzed direct esterification of carboxylicacids and alcohols with high selectivity toward the formation of esters in good to excellent yields. Our results clearly show that HAP@AEPH2-SO3H can be easily recovered by simple filtration and reused for subsequent five runs without any significant impact on yields of products. The main advantage of this methodology is easy and ecofriendly catalyst preparation
Solvent and Structural Effects on the Activation Parameters of the Reaction of Carboxylic Acids with Diazodiphenylmethane
作者:J. B. Nikolić、G. S. Ušćumlić
DOI:10.1002/kin.20762
日期:2013.4
The kinetics of the reaction of benzoic, 2‐methylbenzoic, phenylacetic, cyclohex‐1‐enecarboxylic, 2‐methylcyclohex‐1‐enecarboxylic, and cyclohex‐1‐eneacetic acids with diazodiphenylmethane was studied at 30, 33, 37, 40, and 45°C in a set of 12 protic and aproticsolvents. The reactions were found to follow the second‐order kinetics. The activation energy as well as the activation parameters, such as
Catalytic Asymmetric Diarylphosphine Addition to α-Diazoesters for the Synthesis of P-Stereogenic Phosphinates via P*—N Bond Formation
作者:László B. Balázs、Yinhua Huang、Jasmina B. Khalikuzzaman、Yongxin Li、Sumod A. Pullarkat、Pak-Hing Leung
DOI:10.1021/acs.joc.0c00181
日期:2020.11.20
The asymmetric catalytic P–H addition of racemic secondary phosphines to electrophilic α-diazoesters via P*—N bond formation is disclosed for the first time. Interaction between the diazoester and the palladium catalyst resulted in the unusually enhanced electrophilic ability of the terminal nitrogen in the diazo functionality, as opposed to the commonly expected formation of a metal carbene by nitrogen
Herstellung und Hydrogenolyse von Benzhydrylestern
作者:E. Hardegger、Z. El Heweihi、F. G. Robinet
DOI:10.1002/hlca.19480310220
日期:——
Die Herstellungvon Benzhydrylestern aus Carbonsäuren und Diphenyldiazomethan wurde rnit der Absicht durchgeführt, den für den Ablauf chemischer Reaktionen oft störenden Einfluss freier Carboxylgruppen vorübergehend auszuschalten. Aus den Benzhydrylestern lassen sich, von wenigen Ausnahmen abgesehen, die ursprünglichen Säuren durch Hydrogenolyse rnit Wasserstoff in Gegenwart von Palladium-Kohle regenerieren