Copper-catalyzed cyclopropanation reaction of but-2-ene

Angulo, B. ; Herrerías, C.I. (Universidad de Zaragoza) ; Hormigón, Z. (Universidad de Zaragoza) ; Mayoral, J.A. (Universidad de Zaragoza) ; Salvatella, L. (Universidad de Zaragoza)

Resumen: The mechanism of the copper(I)-catalyzed cyclopropanation reaction for methyl diazoacetate with both (Z)- and (E)-but-2-ene stereoisomers has been studied using the 6-311++G(d, p) basis set by means of M06-2X and O3LYP functionals. According to both methods, the rate-limiting step is the formation of a copper-carbene intermediate, formed by association between methyl diazoacetate and bis(acetonitrile)-copper(I) ion with the concomitant extrusion of dinitrogen. Cis/trans diastereoselectivity for the cyclopropanation reaction of a 1, 2-disubstituted alkene ((Z)-but-2-ene) has been theoretically studied for the first time through the proper location of transition states on the potential-energy surface with the O3LYP method, since no transition structures could be found with the M06-2X functional due to the extreme flatness of the potential-energy surface. The calculated stereoselectivities involving two acetonitrile ligands or one dichloromethane molecule show qualitative agreement with experimental data. This study allows attributing the origin of the selectivity to steric interactions between the ligands of the catalyst system and the olefin substituents. The comparison between the corresponding activation barriers for the direct insertion step shows a higher reactivity for the Z stereoisomer of but-2-ene, consistently with the larger reactant destabilization through steric interactions.

Idioma: Inglés

DOI: 10.1007/s00894-018-3737-1

Año: 2018

Publicado en: JOURNAL OF MOLECULAR MODELING 24 (2018), [8 pp]
ISSN: 1610-2940

Factor impacto JCR: 1.335 (2018)

Categ. JCR: CHEMISTRY, MULTIDISCIPLINARY rank: 122 / 172 = 0.709 (2018) - Q3 - T3
Categ. JCR: COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS rank: 85 / 106 = 0.802 (2018) - Q4 - T3
Categ. JCR: BIOCHEMISTRY & MOLECULAR BIOLOGY rank: 262 / 294 = 0.891 (2018) - Q4 - T3
Categ. JCR: BIOPHYSICS rank: 59 / 72 = 0.819 (2018) - Q4 - T3

Factor impacto SCIMAGO: 0.37 - Catalysis (Q3) - Computational Theory and Mathematics (Q3) - Physical and Theoretical Chemistry (Q3) - Inorganic Chemistry (Q3) - Organic Chemistry (Q3) - Computer Science Applications (Q3)

Financiación: info:eu-repo/grantAgreement/ES/MINECO/CTQ2014-52367-R

Tipo y forma: Article (PostPrint)

Área (Departamento): Área Química Orgánica (Dpto. Química Orgánica)