caa a22 4500 463238818 CHVBK 20180405153306.0 cr unu---uuuuu 170326e20070101xx s 000 0 eng 10.1007/s10947-007-0006-z doi (NATIONALLICENCE)springer-10.1007/s10947-007-0006-z Quantum chemical study of the effect of N,N-acyl group nature on the structure and Gibbs free energy of the sulfur ketoylides and products of their transformations [Elektronische Daten] [D. Chuvashov, I. Vakulin, R. Talipov, F. Galin] With the purpose to study the effect of the nature of the imido-group of N,N-acyl-protected β-methyl-substituted keto-stabilized sulfonium ylides on the formation of methylthiopyrrolisinediones by cyclization, the structure features of these ylides are investigated by ab initio methods. The imido-group nature is shown to insignificantly affect in most cases the structure and the relative free energy of conformers of the ketoylides in question and the products of a cyclization reaction with their participation. The energy difference between the anti-peri-planar and syn-clinal orientation of nitrogen atoms in the imido-group and ylide carbon atom is negligible. The latter orientation is necessary for the reaction of intramolecular cyclization to proceed because in this case carbon atoms between which the bond forms are drawn together. The structure of cyclic pentanomial N,N-acyl group slightly affects the calculated values of Gibbs free energy of sulfur ketoylide reactions, and a temperature increase promotes the intramolecualr cyclization reactions. Wittig and Corey-Chaykovsky reactions typical of ylides are the least thermodynamically favorable for the sulfonium ketoylides under study. Springer Science+Business Media, Inc., 2007 conformation analysis nationallicence sulfonium ylides nationallicence Gibbs free energy nationallicence intramolecular cyclization nationallicence effect nationallicence imido-group nationallicence non-empirical study nationallicence Chuvashov D. Bashkir State University, Ufa aut Vakulin I. Bashkir State University, Ufa aut Talipov R. Bashkir State University, Ufa aut Galin F. Bashkir State University, Ufa aut Journal of Structural Chemistry Kluwer Academic Publishers-Consultants Bureau 48/1(2007-01-01), 37-45 0022-4766 48:1<37 2007 48 10947 https://doi.org/10.1007/s10947-007-0006-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10947-007-0006-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Chuvashov D. Bashkir State University, Ufa aut NATIONALLICENCE 700 1- Vakulin I. Bashkir State University, Ufa aut NATIONALLICENCE 700 1- Talipov R. Bashkir State University, Ufa aut NATIONALLICENCE 700 1- Galin F. Bashkir State University, Ufa aut NATIONALLICENCE 773 0- Journal of Structural Chemistry Kluwer Academic Publishers-Consultants Bureau 48/1(2007-01-01), 37-45 0022-4766 48:1<37 2007 48 10947 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer