Theoretical study of the reactivity of Cl2AlCH2Cl cyclopropanation reagents with olefins in THF solvent

Theoretical Study on Cyclopropanation of endo-Dicyclopentadiene with Zinc Carbenoids: Effects of Solvent and (ICH2)2Zn

“…This result is in agreement with the reports that monomeric Ti, Zn, Al, Sm, and Li carbenoids with low symmetry react with ethylene in an asynchronous manner. [17][18][19]27 Furthermore, the planar ethylene moiety undergoes significant pyramidalization (5.57°and 21.25°for C 2 , 4.71°and 19.85°for C 3 in TS1 and TS2, respectively), which demonstrates that the sp 2 →sp 3 rehybridization of C 2 and C 3 is required for the formation of the cyclopropane ring.…”

“…Bernardi used DFT method to investigate the reaction between ClCH 2 ZnCl and ethene and found that the concerted methylene-transfer channel has a lower barrier with respect to the insertion channel . Nakamura reported that methlyene-transfer represents the reaction reality for the cylcopropanation of ethene with LiCH 2 Cl or ClZnCH 2 Cl. , Recent calculations also suggest that the methylene-transfer pathway is dominant in cyclopropanation using aluminum carbenoids. − Furthermore, some researchers elucidated the influence of carbenoid structure on the cyclopropanation. Zhao reported that geminal dizinc carbenoids (RZn) 2 CHI (R = Et or I) can substantially lower the reaction barrier, compared with monomeric zinc carbenoids .…”