共查询到20条相似文献,搜索用时 13 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
研究了离子液体中Mn(TFPP)Cl(meso-tatrakis(pentafluoropheyl)porphinato)manganese(Ⅲ)cloride锰卟啉催化烯烃的氧化反应.在离子液体-CH2C12混合溶剂中,以价廉、环境友好的H2O2为氧源,考察了离子液体结构、反应条件等对环氧化反应的影响.当氧化剂/环己烯/催化剂/咪唑=450∶150∶1∶75(摩尔比)时,室温下,在MMISM-CH2Cl2的混合溶剂中,环己烯的转化率和环氧环己烷的选择性可分别达到94.8%和95.5%,远高于在纯CH2Cl2中的实验结果.并在最优反应条件下考察了该催化剂体系对烯烃底物的适用性.此外,反应结束后,产物可以由正己烷萃取出来,考察了混合溶剂中Mn(TFPP)Cl催化剂的重复使用情况. 相似文献
12.
13.
Masao Morimoto Tomoya Miura Masahiro Murakami 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(43):12850-12854
Aliphatic terminal alkenes react with pinacolborane at ambient temperature to afford dehydrogenative borylation compounds as the major product when iPr‐Foxap is used as the ligand with cationic rhodium(I) in the presence of norbornene, which acts as the sacrificial hydrogen acceptor. The reaction is applied to the one‐pot syntheses of aldehydes and homoallylic alcohols from aliphatic terminal alkenes. 相似文献
14.
Balzs Budai Alexandre Leclair Qian Wang Jieping Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(30):10411-10415
Reported here is a copper‐catalyzed 1,2‐methoxy methoxycarbonylation of alkenes by an unprecedented use of methyl formate as a source of both the methoxy and the methoxycarbonyl groups. This reaction transforms styrene and its derivatives into value‐added β‐methoxy alkanoates and cinnamates, as well as medicinally important five‐membered heterocycles, such as functionalized tetrahydrofurans, γ‐lactones, and pyrrolidines. A ternary β‐diketiminato‐CuI‐styrene complex, fully characterized by NMR spectroscopy and X‐ray crystallographic analysis, is capable of catalyzing the same transformation. These findings suggest that pre‐coordination of electron‐rich alkenes to copper might play an important role in accelerating the addition of nucleophilic radicals to electron‐rich alkenes, and could have general implications in the design of novel radical‐based transformations. 相似文献
15.
16.
Youxiang Jin Chuan Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6794-6798
Reported is an asymmetric reductive dicarbofunctionalization of unactivated alkenes. Under the catalysis of a Ni/BOX system, various aryl bromides, incorporating a pendant olefinic unit, were successfully reacted with an array of primary alkyl bromides in the presence of Zn as a reductant, furnishing a series of benzene‐fused cyclic compounds bearing a quaternary stereocenter in high enantioselectivities. Notably, this reaction avoids the use of pregenerated organometallics and demonstrates high tolerance of sensitive functionalities. The preliminary mechanistic investigations reveal that this Ni‐catalyzed reaction proceeds as a cascade consisting of migratory insertion and cross‐coupling with a nickel(I)‐mediated intramolecular 5‐exo cyclization as the enantiodetermining step. 相似文献
17.
18.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(35):10691-10694
A copper‐catalyzed three‐component reaction of alkenes, acetonitrile, and sodium azide afforded γ‐azido alkyl nitriles by formation of one C(sp3)−C(sp3) bond and one C(sp3)−N bond. The transformation allows concomitant introduction of two highly versatile groups (CN and N3) across the double bond. A sequence involving the copper‐mediated generation of a cyanomethyl radical and its subsequent addition to an alkene, and a C(sp3)−N bond formation accounted for the reaction outcome. The resulting γ‐azido alkyl nitrile can be easily converted into 1,4‐diamines, γ‐amino nitriles, γ‐azido esters, and γ‐lactams of significant synthetic value. 相似文献
19.
Bianca Bitterlich Gopinathan Anilkumar Dr. Feyissa Gadissa Gelalcha Dr. Björn Spilker Dr. Anne Grotevendt Ralf Jackstell Dr. Man Kin Tse Dr. Matthias Beller Prof. Dr. 《化学:亚洲杂志》2007,2(4):521-529
The development of inexpensive and practical iron catalysts for the environmentally benign epoxidation of olefins with hydrogen peroxide as terminal oxidant is described. By systematic variation of ligands, metal sources, and reaction conditions, it was discovered that FeCl3?6H2O in combination with pyridine‐2,6‐dicarboxylic acid and different amines shows high reactivity and excellent selectivity towards the epoxidation of aromatic olefins and moderate reactivity towards that of aliphatic olefins. 相似文献
20.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(43):13499-13503
A method for the copper‐catalyzed borylacylation of activated alkenes is presented. The reaction involves borylcupration of the alkene, followed by capture of the generated alkyl–copper intermediate with an acid chloride. The reactions operated with low catalyst loading and generally occurre within 15 min at room temperature for a range of activated alkenes. In the case of vinyl arenes, enantioselective borylacylation was possible. 相似文献