title: Two approaches to diverting the course of a free-radical cyclization: application of cyclopropylcarbinyl radical fragmentations and allenes as radical acceptors.
abstract: Free radical cyclization of 4 and 7 gave the expected cyclization-reduction products (5 and 8) along with considerable amounts of products derived from a cyclization-atom transfer-secondary cyclization process (6 and 9). Two approaches to avoiding these unexpected products were explored. Use of a cyclopropylcarbinyl fragmentation avoided the secondary cyclization reaction (25 or 43 --> 26 or 44), whereas use of an allene as a radical acceptor avoided the atom-transfer reaction altogether (49 --> 52).
authors.affiliation: Department of Chemistry, The Ohio State University 100 West 18th Avenue, Columbus, Ohio 43210, USA.
authors.forename: Dexi
authors.initials: D
authors.lastname: Yang
authors.forename: Valerie
authors.initials: V
authors.lastname: Cwynar
authors.forename: Matthew G
authors.initials: MG
authors.lastname: Donahue
authors.forename: David J
authors.initials: DJ
authors.lastname: Hart
authors.forename: Grace
authors.initials: G
authors.lastname: Mbogo
mesh_terms: D000473:Alkanes / Q000737:chemistry*; D003500:Cyclization; D003521:Cyclopropanes / Q000138:chemical synthesis* / Q000737:chemistry; D005609:Free Radicals / Q000138:chemical synthesis / Q000737:chemistry; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D000473:Alkanes; D003521:Cyclopropanes; D005609:Free Radicals