title: Titanium carbenoid-mediated cyclopropanation of allylic alcohols: selectivity and mechanism.
abstract: A new method for the chemo- and stereoselective conversion of allylic alcohols into the corresponding cyclopropane derivatives has been developed. The cyclopropanation reaction was carried out with an unprecedented titanium carbenoid generated in situ from Nugent's reagent, manganese and methylene diiodide. The reaction involving the participation of an allylic hydroxyl group, proceeded with conservation of the alkene geometry and in a high diastereomeric excess. The scope, limitations and mechanism of this metal-catalysed reaction are discussed.
authors.affiliation: Departamento de Química Orgánica, Facultad de Ciencias, Campus Universitario Río San Pedro s/n, Torre sur, 4° planta, Universidad de Cádiz, 11510, Puerto Real, Cádiz, Spain. isidro.gonzalez@uca.es.
authors.forename: M J
authors.initials: MJ
authors.lastname: Durán-Peña
authors.forename: J M
authors.initials: JM
authors.lastname: Botubol-Ares
authors.forename: J R
authors.initials: JR
authors.lastname: Hanson
authors.forename: R
authors.initials: R
authors.lastname: Hernández-Galán
authors.forename: I G
authors.initials: IG
authors.lastname: Collado
mesh_terms: D003521:Cyclopropanes / Q000138:chemical synthesis* / Q000737:chemistry; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D020005:Propanols / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D003521:Cyclopropanes; D020005:Propanols; C030011:carbene; C006463:allyl alcohol; D014025:Titanium; D008697:Methane