title: Photochemical synthesis of phosphinolines from phosphonium-iodonium ylides.
abstract: We describe three different series of experiments which were undertaken to test our hypothesis that during irradiation of phosphonium-iodonium ylides (1a, 1b) an electrophilic carbene is generated. By opposing the assumed intermediate to monosubstituted alkynes, we observed in the case of electron-rich substituents at the triple bond a domination of a 1,3-dipolar cycloaddition of the intermediate with the triple bond to yield furans. In the case of electron poorer substituents, the formation of phosphinolines prevails. A second series of experiments was carried out with mixed ylides in which one phenyl ring at the triarylphosphonium group was replaced by a thienyl group. In this case, we observe only an intramolecular reaction with the thienyl ring to yield the phosphinolines 21-23. In a third test, we replaced in the mixed ylides 1a, 1b the COR group by a CN substituent. This modification leads to phosphinolines only and avoids a 1,3-dipolar cycloaddition.
authors.affiliation: Department of Chemistry, Moscow State Lomonosov University, Moscow, Lenin Hills, 1, Russian Federation 119992. matveeva@org.chem.msu.ru
authors.forename: Elena D
authors.initials: ED
authors.lastname: Matveeva
authors.forename: Tatyana A
authors.initials: TA
authors.lastname: Podrugina
authors.forename: Marina A
authors.initials: MA
authors.lastname: Taranova
authors.forename: Anatolyi A
authors.initials: AA
authors.lastname: Borisenko
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Mironov
authors.forename: Rolf
authors.initials: R
authors.lastname: Gleiter
authors.forename: Nikolay S
authors.initials: NS
authors.lastname: Zefirov