78548-59-1Relevant academic research and scientific papers
Cyclopropanation of olefins by ethyl diazoacetate: copper- and copper-complex-containing X-zeolites as the catalysts
Oudejans, J.C.,Kaminska, J.,Dalen, A. C. Kock-van,Bekkum, H. van
, p. 421 - 427 (2007/10/02)
Cyclopropanation of olefins by ethyl diazoacetate has been carried out making use of the catalytic action of Cu-loaded X-type zeolites upon the decomposition of ethyl diazoacetate.The activity of the NaCuX zeolites is linearly dependent upon the Na-exchange level.Compared to conventional copper catalysts, the zeolite catalysts give rise to relatively low amounts of polymeric side-product which is assumed to be formed at the outer zeolite surface.The stereoselectivity obtained with the zeolite catalysts does not deviate significantly from that obtained using copper salts.Zeolite X, loaded with chiral copper complexes, gives rise to only minor asymmetric induction upon cyclopropanation of 1,1-dichloro-4-methyl-1,3-pentadiene with ethyl diazoacetate.
Ester synthesis
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, (2008/06/13)
A novel process is described for the preparation of compounds of formula STR1 wherein R2 and R3 are each chloro or bromo; X is carboxyl, nitrile, optionally substituted carbonamide, carbonyl halide or an ester group. Those compounds wherein X is an appropriate ester group --COOB where B is an aryl group such as m-phenoxybenzyl are known insecticides; compounds where X is other than --COOB may be suitably converted thereto. The novel process consists of a series of steps from the corresponding acetyl compound of formula STR2 which comprises halogenation, reduction, esterification and finally elimination reactions.
