cis-2-Alkylcyclohexanols are obtained stereoselectively upon irradiation of a mixture of cyclohexene and the corresponding trialkylborane in the presence of p-xylene as a sensitizer and upon the successive oxidation of the photolysate with alkaline H2O2. The similar reaction of 1-ethylcyclohexene yields 2,2-dialkylcyclohexanols. Cycloheptene also reacts with the boranes to afford cis-2-alkylcycloheptanols
在对二甲苯作为敏化剂的存在下,对环己烯和相应的三烷基硼烷的混合物进行辐照,然后用碱性H 2 O 2连续氧化光解产物,可通过立体选择获得顺式-2-烷基环己醇。1-乙基环己烯的类似反应产生2,2-二烷基环己醇。环庚烯还与硼烷反应以提供顺式-2-烷基环庚醇。通过假定高度应变的反式-环己烯或-庚烯为反应性物质来解释这些反应。光化学产生的反式-环-辛-2-烯酮和顺式,反式-环-辛基-2,7-二烯酮与硼热反应,分别得到3-烷基环辛酮和顺式-7-烷基环辛-2-烯酮。cr啶与硼烷的光反应导致还原性烷基化,以相当好的收率得到9-烷基ac啶。
Mass spectrometry in structural and stereochemical problems—CXXII
作者:J.K. MacLeod、J.B. Thomson、Carl Djerassi
DOI:10.1016/0040-4020(67)80042-5
日期:1967.5
A study of the double McLafferty transfer process in the massspectra of two cyclicketones and a substituted malonic ester, at both high and low electron energies, has shown that little tautomerism of the intermediate single McLafferty enolateion occurs in these cases.
Diastereoselective Construction of Fused Carbocyclic Pyrrolidines via a Copper-Catalyzed [3 + 2] Cycloaddition: Total Syntheses of Pancratinines B–C
作者:Fang Wang、Xiaohan Xu、Yangtian Yan、Jiayang Zhang、Wen-Ju Bai、Jianwei Chen、Yang Yang
DOI:10.1021/acs.orglett.3c02310
日期:2023.9.22
A Cu-catalyzed diastereoselective [3 + 2] cycloaddition of 2-arylaziridines and cyclic silyl dienol ethers was developed to efficiently construct fused-[5,n] carbocyclic pyrrolidines, which are widespread in bioactive natural products. Mechanistic studies revealed that the high diastereoselectivity of this transformation arose from a sequential retro aza-Michael/epimerization/aza-Michael process. Taking
开发了铜催化的2-芳基氮丙啶和环状甲硅烷基二烯醇醚的非对映选择性[3 + 2]环加成反应,以有效构建稠合-[5, n ]碳环吡咯烷,该化合物广泛存在于生物活性天然产物中。机理研究表明,这种转化的高非对映选择性源于连续的逆向氮杂迈克尔/差向异构化/氮杂迈克尔过程。利用这种新开发的方法,首次实现了 pancratinines B 和 C 的全合成。
COMPOSITION FOR TOPICAL APPLICATION
申请人:INSTITUTE FOR ADVANCED SKIN RESEARCH INC.
公开号:EP0745389A1
公开(公告)日:1996-12-04
A composition for topical application comprising at least one surfactant having a nitrogen atom in the moiety thereof and at least one compound selected from the group consisting of cyclohexane and the derivatives thereof, cyclohexene and the derivatives thereof, and cyclohexanone and the derivatives thereof.
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.