caa a22 4500 605512434 CHVBK 20210128100655.0 cr unu---uuuuu 210128e20150401xx s 000 0 eng 10.1007/s00894-015-2571-y doi (NATIONALLICENCE)springer-10.1007/s00894-015-2571-y Theoretical study of the Wittig reaction of cyclic ketones with phosphorus ylide [Elektronische Daten] [Nisha Jarwal, Pompozhi Thankachan] The Wittig reaction of cyclopropanone, cyclobutanone and cyclopentanone with phosphorus ylide (Me3P = CH2) in gas phase was investigated computationally at B3LYP/6-31G** level of theory. In the Wittig reaction of cyclic ketones, two transition states (TS1 and TS2), corresponding to formation and decomposition of oxaphosphetane (OP) were located and investigated. Two loosely bound intermediates, a reactant complex (RC) and a product complex (PC) were also found. In the reaction of cyclopropanone, cyclobutanone and cyclopentanone, two oxaphosphetanes (OP1 and OP2) were predicted. OP1 initially formed was converted into OP2 by pseudorotation. In contrast to the reactions with cyclobutanone and cyclopentanone, an early TS1 was found in the reaction of cyclopropanone. The order of first activation energy barrier relative to reactant total energy was found to be cyclopropanone (−4.97kcalmol−1) < cyclobutanone (0.30kcalmol−1) < cyclopentanone (3.60kcalmol−1). Graphical Abstract The Wittig reaction of monocyclic ketones with phosphorus ylide Me3PCH2. Springer-Verlag Berlin Heidelberg, 2015 Wittig reaction nationallicence Cyclopropanone nationallicence Cyclobutanone nationallicence Cyclopentanone nationallicence Cyclic ketones nationallicence Jarwal Nisha Department of Chemistry, Indian Institute of Technology Roorkee, 247 667, Roorkee, India aut Thankachan Pompozhi Department of Chemistry, Indian Institute of Technology Roorkee, 247 667, Roorkee, India aut Journal of Molecular Modeling Springer Berlin Heidelberg 21/4(2015-04-01), 1-8 1610-2940 21:4<1 2015 21 894 https://doi.org/10.1007/s00894-015-2571-y text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00894-015-2571-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Jarwal Nisha Department of Chemistry, Indian Institute of Technology Roorkee, 247 667, Roorkee, India aut NATIONALLICENCE 700 1- Thankachan Pompozhi Department of Chemistry, Indian Institute of Technology Roorkee, 247 667, Roorkee, India aut NATIONALLICENCE 773 0- Journal of Molecular Modeling Springer Berlin Heidelberg 21/4(2015-04-01), 1-8 1610-2940 21:4<1 2015 21 894