Reduction of activated ketals with borane-dimethyl sulphide
摘要:
Borane-Dimethyl sulphide reduces ketals activated with TMSOTf at -78-degrees-C in dichloromethane. The scope and selectivity of the reagent has been investigated.
A selectivity study of activated ketal reduction with borane dimethyl sulfide
摘要:
A chemo- and regioselectivity study of the reagent combination BH3.SMe2/TMSOTf for ketal reduction has been undertaken. It has revealed that simple 1,3-dioxanes reduce cleanly at low temperature in CH2Cl2 while simple 1,3-dioxolanes may give complete ring cleavage and dimerization products. A study of reduction of 4-substituted 1,3-dioxolanes has revealed a solvent-directed regioselectivity which in THF favors the secondary protected derivative. A mechanism is postulated to account for the selectivities based on recent thinking on acetal substitution reactions.
Bartels Birgit, Hunter Roger, J. Org. Chem, 58 (1993) N 24, S 6756-6765
作者:Bartels Birgit, Hunter Roger
DOI:——
日期:——
SOLID CATALYST FOR OLEFIN POLYMERIZATION AND PROCESS FOR PRODUCING OLEFIN POLYMER
申请人:Sumitomo Chemical Company, Limited
公开号:US20130072648A1
公开(公告)日:2013-03-21
A solid catalyst for olefin polymerization and a process for producing an olefin polymer are provided. The polymer has a small content of a component which is dissolved out into a low temperature organic solvent, such as a low-molecular weight component and an amorphous component. The solid catalyst is obtained by bringing a solid catalyst component for olefin polymerization containing a titanium atom, a magnesium atom, a halogen atom, and an aliphatic carboxylate; an organoaluminum compound; and a compound represented by formula (I) into contact with each other:
wherein R
1
is a hydrocarbyl group having 1 to 10 carbon atoms, R
2
is a hydrogen atom, a halogen atom or a hydrocarbyl group having 1 to 16 carbon atoms, and the R
1
the R
2
groups are independently the same or different, and the respective R
1
groups and R
2
groups may be joined with each other to form a ring.
ELECTROLYTIC SOLUTION FOR LITHIUM-ION SECONDARY BATTERY, AND LITHIUM-ION SECONDARY BATTERY
申请人:Murata Manufacturing Co., Ltd.
公开号:US20210226253A1
公开(公告)日:2021-07-22
A lithium-ion secondary battery includes a positive electrode, a negative electrode, and an electrolytic solution. The electrolytic solution includes a solvent, an electrolyte salt, and at least one of a first dioxane compound or a second dioxane compound.