The stereochemistry of 1,3-dipolar cycloaddition of C-methyl-N-phenylnitrone I with substituted styrenes has been investigated. The presence of an hydroxyl function at the ortho position Lt the dipolarophile completely controls the stereochemical course of the reaction with the exclusive formation of cycloadduct 7. MNDO calculations help to rationalise the obtained results on the basis of an intermolecular hydrogen bonding, which leads to changes irt the FMO properties so improving a stabilizing secondary orbital interaction in the E-endo transition stare leading to cis isomer.
The stereochemistry of 1,3-dipolar cycloaddition of C-methyl-N-phenylnitrone I with substituted styrenes has been investigated. The presence of an hydroxyl function at the ortho position Lt the dipolarophile completely controls the stereochemical course of the reaction with the exclusive formation of cycloadduct 7. MNDO calculations help to rationalise the obtained results on the basis of an intermolecular hydrogen bonding, which leads to changes irt the FMO properties so improving a stabilizing secondary orbital interaction in the E-endo transition stare leading to cis isomer.
STEREOSELECTIVE CONTROL IN 1,3-DIPOLAR CYCLOADDITION OF NITRONES TO SUBSTITUTED STYRENES
CHIACCHIO, Ugo;RESCIFINA, Antonio;
1994-01-01
Abstract
The stereochemistry of 1,3-dipolar cycloaddition of C-methyl-N-phenylnitrone I with substituted styrenes has been investigated. The presence of an hydroxyl function at the ortho position Lt the dipolarophile completely controls the stereochemical course of the reaction with the exclusive formation of cycloadduct 7. MNDO calculations help to rationalise the obtained results on the basis of an intermolecular hydrogen bonding, which leads to changes irt the FMO properties so improving a stabilizing secondary orbital interaction in the E-endo transition stare leading to cis isomer.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
