Copper Mediated Formation of Carbon-Heteroatom Bonds Using Organoboron Reagents and Ultrasound
摘要:
This report summarizes research efforts focused on copper acetate mediated reactions to form new carbon-heteroatom bonds using organoboron reagents under ultrasound irradiation. The method involves the application of ultrasound irradiation to the Chan-Evans-Lam reaction to achieve O-arylation of phenols, N-arylation of anilines and indoles, and S-arylation of thiols. Ultrasound irradiation was found to decrease reaction times from 72 hours to 4 hours while improving the product yields an average of 20%(1) Representative C-O, C-N, and C-S coupling reactions were successfully scaled-up from the milligram to gram levels while maintaining good product yields offering potential applications in industrial processes.
FLAME-RETARDANT POLYCARBONATE RESIN COMPOSITION AND ELECTRICAL AND ELECTRONIC COMPONENTS MADE BY MOLDING THE SAME
申请人:——
公开号:US20020077417A1
公开(公告)日:2002-06-20
A flame-retardant polycarbonate resin composition, characterized by comprising a polycarbonate resin (A) and a composite rubbery graft copolymer (B), preferably one obtained by grafting a composite rubber having a structure constituted of 1 to 99 wt. % of a polyorganosiloxane rubber component and 99 to 1 wt. % of a polyalkyl acrylate rubber component, the two components being so interwisted with each other as not to separate from each other, and a mean particle diameter of 0.01 to 0.6 &mgr;m with one or more vinyl monomers, at an (A) to (B) weight ratio of 99:1 to 90:10, and by containing, per 100 parts by weight of the sum total of the components (A) and (B), 0.3 to 1.2 parts by weight (in terms of phosphorus) of a halogen-free phosphoric ester (C) and 0.01 to 1.0 part by weight of polytetrafluoroethylene (D), the weight ratio of the graft copolymer (B) to the phosphorus resulting from the phosphoric ester (C) lying within the range of 2 to 15; and housing of office automation equipment and electrical and electronic appliances and battery packs made by molding the composition. The composition is improved in mechanical properties such as impact resistance, is excellent in moldability and flowability, and exhibits high flame retardance even without resort to any bromine compound.
Copper Mediated Formation of Carbon-Heteroatom Bonds Using Organoboron Reagents and Ultrasound
作者:George W. Kabalka、Bryan J. Musolino
DOI:10.3987/com-14-s(k)18
日期:——
This report summarizes research efforts focused on copper acetate mediated reactions to form new carbon-heteroatom bonds using organoboron reagents under ultrasound irradiation. The method involves the application of ultrasound irradiation to the Chan-Evans-Lam reaction to achieve O-arylation of phenols, N-arylation of anilines and indoles, and S-arylation of thiols. Ultrasound irradiation was found to decrease reaction times from 72 hours to 4 hours while improving the product yields an average of 20%(1) Representative C-O, C-N, and C-S coupling reactions were successfully scaled-up from the milligram to gram levels while maintaining good product yields offering potential applications in industrial processes.