Regiochemistry of the ring expansion of unsymmetrically substituted ketones involving β-hydroxyalkylselenides
作者:A. Krief、J.L. Laboureur
DOI:10.1016/s0040-4039(01)81038-8
日期:1987.1
β-hydroxyalkylselenides derivedfrom unsymmetrically substituted ketones have been rearranged to substituted ketones in the presence of soft electrophiles such as silver tetrafluoraborate or dichlorocarbenes. Although the migration of the more substituted carbon often prevails, subtle variations have been observed depending upon the structure of the starting material and the experimental conditions
Total Synthesis of Himachalene Sesquiterpenes of<i>Aphthona</i>and<i>Phyllotreta</i>Flea Beetles
作者:Robert J. Bartelt、David Weisleder、Frank A. Momany
DOI:10.1055/s-2003-36253
日期:——
A totalsynthesis is presented for himachalene-related norsesquiterpene ketone 1 (racemic), based on the Robinson annulation and other standard reactions. The route involved five steps from cycloheptanone. A favorable result was that the desired diastereomer of 1 was obtained preferentially (97:3) over the unwanted one. Molecular modeling (ab initio calculations) aided in confirming the assignment
COPOLYMER, METHOD FOR PRODUCING SAME, RESIN MATERIAL FOR ELECTRIC WIRE SHEATHING, AND ELECTRIC WIRE
申请人:Asahi Glass Company, Limited
公开号:EP3330301A1
公开(公告)日:2018-06-06
To provide an ETFE copolymer and a wire coating resin material capable of forming a coating layer which is excellent in stress cracking resistance under a high temperature and which has a high heat resistance temperature, and an electric wire having a coating layer which is excellent in stress cracking resistance under a high temperature and which has a high heat resistance temperature. A copolymer comprising structural units derived from ethylene, structural units derived from tetrafluoroethylene, and structural units derived from a third monomer, wherein in an elution curve obtained by a temperature rising elution fractionation method with respect to the copolymer, a ratio (L/H) of a proportion (L: area%) of components with elution temperatures of from 190 to 200°C to a proportion (H: area%) of components with elution temperatures of at least 205°C, and a proportion (M: mol%) of structural units derived from the third monomer based on all structural units of the copolymer, satisfy a relation of log (L/H)/M≧0.90.
Copolymer, method for its production, wire coating resin material and electric wire
申请人:AGC Inc.
公开号:US10607749B2
公开(公告)日:2020-03-31
To provide an ETFE copolymer and a wire coating resin material capable of forming a coating layer which is excellent in stress cracking resistance under a high temperature and which has a high heat resistance temperature, and an electric wire having a coating layer which is excellent in stress cracking resistance under a high temperature and which has a high heat resistance temperature. A copolymer comprising structural units derived from ethylene, structural units derived from tetrafluoroethylene, and structural units derived from a third monomer, wherein in an elution curve obtained by a temperature rising elution fractionation method with respect to the copolymer, a ratio (L/H) of a proportion (L: area %) of components with elution temperatures of from 190 to 200° C. to a proportion (H: area %) of components with elution temperatures of at least 205° C., and a proportion (M: mol %) of structural units derived from the third monomer based on all structural units of the copolymer, satisfy a relation of log (L/H)/M≥0.90.