A highly efficient heterogeneous copper-catalyzed Chan-Lam coupling between thiols and arylboronic acids leading to diaryl sulfides under mild conditions
作者:Yang Lin、Mingzhong Cai、Zhiqiang Fang、Hong Zhao
DOI:10.1016/j.tet.2016.04.063
日期:2016.6
coupling reaction between thiols and arylboronicacids was achieved in EtOH at room temperature in the presence of 5 mol % of MCM-41-immobilized 1,10-phenanthroline-copper(II) complex [MCM-41-1,10-Phen-CuSO4] with n-Bu4NOH (40% aq) as base under O2 atmosphere, yielding a variety of unsymmetrical diaryl sulfides in good to excellent yields under mild and green conditions. The new heterogeneous copper complex
A Robust Pd-Catalyzed C–S Cross-Coupling Process Enabled by Ball-Milling
作者:Andrew C. Jones、William I. Nicholson、Harry R. Smallman、Duncan L. Browne
DOI:10.1021/acs.orglett.0c02418
日期:2020.10.2
operationally simple mechanochemical C–S coupling of aryl halides with thiols has been developed. The reaction process operates under benchtop conditions without the requirement for a (dry) solvent, an inert atmosphere, or catalyst preactivation. The reaction is finished within 3 h. The reaction is demonstrated across a broad range of substrates; the inclusion of zinc metal has been found to be critical in
Curable mixtures of polyepoxides and amine-terminated graft polymer dispersions
申请人:BASF WYANDOTTE CORPORATION
公开号:EP0059369A1
公开(公告)日:1982-09-08
Curable mixtures of polyepoxides and amine-terminated polymers are employed. The amine-terminated polymers are prepared by the in situ free radical polymerization of ethylenically unsaturated monomer or monomers in amine-terminated polyoxyalkylene polyether polymers.
胺封端聚合物是通过乙烯不饱和单体或胺封端聚氧亚烷基聚醚聚合物中的单体原位自由基聚合制备的。
Method for the preparation of graft polymer dispersions having broad particle size distribution without wildly fluctuating viscosities
申请人:BASF Corporation
公开号:EP0365986A2
公开(公告)日:1990-05-02
A method for preparing graft polymer dispersions having broad particle size distribution without wildly fluctuating viscosities is disclosed. The method comprises:
(a) preparing intermediate graft polyol dispersions containing 30 percent by weight or less solids to achieve a broad distribution of partial sizes in a continuous process by feeding a sufficient amount of an ethylenically unsaturated monomer and a free radical initiator into a flow reactor at a temperature sufficient to promote polymerization, and
(b) charging the intermediate graft polymer dispersion of (a) to a semi-batch reactor as seeds for further grafting to increase the solids content of the dispersion to above 30 percent by weight by feeding an effective amount of an ethylenically unsaturated monomer and a free radical initiator into the semi-batch reactor at a temperature sufficient to promote the growth of the seeds, whereby the seed particles generally grow larger but retain the characteristic of broad size distribution. The graft polymer so formed is useful in the production of polyurethanes.
A process for preparing a flexible, low density, integral skin polyurethane foam wherein water is used as the sole blowing and density controlling agent. The process entails reacting an isocyanate component with a compound containing isocyanate reactive groups and further containing ether linkages, a polyurethane promoting catalyst, an alcohol, a surfactant, a chain extender and optional additives. The reaction is carried out at molded densities of from 15 pcf to 30 pcf in molds preheated to about 90°F to about 130°F.