A Modular Rearrangement Approach toward Medicinally Relevant Phosphinic Structures
摘要:
An unprecedented coupling of a P-C and a C-C bond-forming event in a practical operation was developed to access medicinally relevant phosphinic structures. The strategy relies on an Ireland-Claisen rearrangement triggered by the phospha-Michael addition of silyl phosphonites to allyl acrylates. This protocol was extended to a more versatile three-component variant that utilizes phosphinic acids, acryloyl chlorides, and allylic alcohols as starting materials.
Method of making alternating copolymers of isobutylene type monomers
申请人:——
公开号:US20030171515A1
公开(公告)日:2003-09-11
A method of making a copolymer composition containing a copolymer, which includes the steps of (a) providing a donor monomer composition that includes an isobutylene type monomer; (b) mixing the donor monomer composition with an ethylenically unsaturated monomer composition that includes one or more ethylenically unsaturated acceptor monomers, and is substantially free of maleate type monomers and fumarate type monomers, and (c) polymerizing the mixture resulting from step (b) in the presence of a free radical polymerization initiator. The polymerization is carried out in the substantial absence of Lewis acids and/or transition metals. The isobutylene type monomer is present at a molar excess of at least 10 mol % based on the molar concentration of monomers in the ethylenically unsaturated monomer composition. The ethylenically unsaturated acceptor monomers are present in an amount of at least 15 mol % of the total monomer composition.