6746-94-7Relevant articles and documents
Evidence for Concert in the Thermal Unimolecular Vinylcyclopropane to Cyclopentene Sigmatropic 1,3-Shift
Gajewski, Joseph J.,Olson, Leif P.,Willcott, M. Robert
, p. 299 - 306 (1996)
Gas phase pyrolysis of cis-2,3-dideuterio-trans-(1'-tert-butyl-2'-(Z)-deuteriovinyl)cyclopropane at 290 deg C gives trans,trans-3,4,5-trideuterio-1-tert-butylcyclopentene as the major 1,3-shift product with greater than 90percent stereospecificity in an orbital symmetry "allowed" suprafacial-inversion sense after correction for the geometric isomerization of starting material and the other materials present.The isotopic substitution at the critical sites of rearrangement eliminates steric of electronic influences of substitutents on a biradical pathway as a source of the suprafacial- inversion stereochemistry observed with more highly substituted drivatives.The stereochemical results coupled with a normal deuterium kinetic isotope effect (kH/2kD=1.14 at 311.6 deg C) at the exo-methylene carbon are best interpreted in terms of a concerted pathway for rearrangement.A less likely alternative is a stereospecific disrotatory ring opening to a biradical followed by rate-determining closure to a five-membered ring.Accompanying the rearrangement is geometric isomerization of starting material resulting from C-1-C-2 bond fission which favors either the single methylene rotation or a double rotation by a factor of 10 over single rotation at the vinyl-bearing carbon.
Brand-new synthetic process route of cyclopropyl acetylene (by machine translation)
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Paragraph 0028-0032, (2020/05/30)
The process route of, is that the raw materials used by the two-step reaction, are easily available, the reaction conditions are mild, no three wastes are generated, the process route, is easy to operate, the yield is high, the yield is high, the, yield is high, and the industrial production, can be realized through the process route of the process route only through the two-step reaction, scheme of, the process, route shown, in the present invention. (by machine translation)
Palladium-Catalyzed Cascade Intramolecular Cyclization and Allylation of Enynoates with Allylic Alcohols
Qiu, Sheng-Qi,Ahmad, Tanveer,Xu, Yun-He,Loh, Teck-Peng
, p. 6729 - 6736 (2019/06/14)
A Pd(II)-catalyzed mild and highly regioselective 6-endo cyclization/allylation reaction of enynoates with simple allylic alcohols has been developed. Under mild reaction conditions, the vinyl palladium species generated in situ after cyclization could insert C-C double bond of allylic alcohol through cross-coupling reaction and lead to the formation of allyl pyrone via β-OH elimination. This cascade cross-coupling reaction represents a direct and atom economic methodology for the construction of novel allyl pyrones in moderate to good yields.
METHOD FOR THE MANUFACTURE OF EFAVIRENZ
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Page/Page column 23, (2018/09/19)
This invention relates to a method for the manufacture of optically pure (S)-6- chloro-(cyclopropylethynyl)-1,4-dihydro-4-(trifluoromethyl)-2H-3,1 -benzoxazin- 2-one. Specifically, this invention relates to a flow synthesis method for the manufacture of (S)-6-chloro-(cyclopropylethynyl)-1,4-dihydro-4- (trifluoromethyl)-2H-3,1 -benzoxazin-2-one.