4442-41-5Relevant articles and documents
Catalytic Activity of an Octopus-type Calixarene on the Formation of Ethers
Taniguchi, Hisaji,Nomura, Eisaku
, p. 1773 - 1776 (1988)
5,11,17,23,29,35-Hexa-p-tert-butyl-37,38,39,40,41,42-hexakis-(3,6,9-trioxadecyloxy)calixarene catalyzes the formation of an ether and bisphenoxymethanes through the Williamson synthesis.
NHC-CDI Betaine Adducts and Their Cationic Derivatives as Catalyst Precursors for Dichloromethane Valorization
Sánchez-Roa, David,Mosquera, Marta E. G.,Cámpora, Juan
, p. 16725 - 16735 (2021/11/18)
Zwitterionic adducts of N-heterocyclic carbene and carbodiimide (NHC-CDI) are an emerging class of organic compounds with promising properties for applications in various fields. Herein, we report the use of the ICyCDI(p-Tol) betaine adduct (1a) and its cationic derivatives2aand3aas catalyst precursors for the dichloromethane valorization via transformation into high added value products CH2Z2(Z = OR, SR or NR2). This process implies selective chloride substitution of dichloromethane by a range of nucleophiles Na+Z-(preformed or generatedin situfrom HZ and an inorganic base) to yield formaldehyde-derived acetals, dithioacetals, or aminals with full selectivity. The reactions are conducted in a multigram-scale under very mild conditions, using dichloromethane both as a reagent and solvent, and very low catalyst loading (0.01 mol %). The CH2Z2derivatives were isolated in quantitative yields after filtration and evaporation, which facilitates recycling the dichloromethane excess. Mechanistic studies for the synthesis of methylal CH2(OMe)2rule out organocatalysis as being responsible for the CH2transfer, and a phase-transfer catalysis mechanism is proposed instead. Furthermore, we observed that1aand2areact with NaOMe to form unusual isoureate ethers, which are the actual phase-transfer catalysts, with a strong preference for sodium over other alkali metal nucleophiles.
Copper Catalyzed sp3 C-H Etherification with Acyl Protected Phenols
Salvador, Tolani K.,Arnett, Charles H.,Kundu, Subrata,Sapiezynski, Nicholas G.,Bertke, Jeffery A.,Raghibi Boroujeni, Mahdi,Warren, Timothy H.
supporting information, p. 16580 - 16583 (2017/01/10)
A variety of acyl protected phenols AcOAr participate in sp3 C-H etherification of substrates R-H to give alkyl aryl ethers R-OAr employing tBuOOtBu as oxidant with copper(I) β-diketiminato catalysts [CuI]. Although 1°, 2°, and 3° C-H bonds may be functionalized, selectivity studies reveal a preference for the construction of hindered, 3° C-OAr bonds. Mechanistic studies indicate that β-diketiminato copper(II) phenolates [CuII]-OAr play a key role in this C-O bond forming reaction, formed via transesterification of AcOAr with [CuII]-OtBu intermediates generated upon reaction of [CuI] with tBuOOtBu.
Synthesis of carbonates directly from 1 atm CO2 and alcohols using CH2Cl2
Yamazaki, Yusuke,Kakuma, Kasumi,Du, Ya,Saito, Susumu
scheme or table, p. 9675 - 9680 (2011/02/24)
We introduced here a new one-pot, general procedure for the preparation of dialkyl carbonates from alcohols in a straightforward fashion under 1 atm pressure of CO2 using Cs2CO3 and CH 2Cl2 as key reagents.
