Towards Axially Chiral Pyrazole‐Based Phosphorus Scaffolds by Dipeptide‐Phosphonium Salt Catalysis
作者:Jia‐Hong Wu、Jian‐Ping Tan、Jia‐Yan Zheng、Jiajia He、Zhenlei Song、Zhishan Su、Tianli Wang
DOI:10.1002/anie.202215720
日期:2023.3.20
enantioselective reaction has been developed for the construction of axially chiral arylpyrazole skeletons with phosphorus unit. The reaction proceeds through a sequential Huisgen-type cycloaddition/aromatization process with central-to-axial chirality conversion using a dipeptide-phosphonium salt catalyst. Arylpyrazole-based atropisomeric phosphorus compounds are obtained in high yields with excellent enantioselectivities
HYDROFLUOROHALOCARBON DECOMPOSITION INHIBITOR AND METHOD
申请人:DAIKIN INDUSTRIES, LIMITED
公开号:EP0669305A1
公开(公告)日:1995-08-30
A hydrochlorofluorocarbon (HCFC) decomposition inhibitor comprising at least one member selected from among a mixture of an organic acid with an amine, a fluorine-free halohydrocarbon, a carboxylic ester, a nitrile compound, a carbonyl compound and a halogenated nitro compound, and a method of inhibiting the decomposition of HCFC with the inhibitor. The inhibitor is effective in inhibiting for long the decomposition of HCFC used as a blowing agent in the production of polyurethane foam during the storage of the feedstock material, in the course of the production of the foam and during the use of the product.