title: Semipinacol rearrangement of cis-fused β-lactam diols into keto-bridged bicyclic lactams.
abstract: The 6-azabicyclo[3.2.1]octane ring system, prevalent in a range of biologically active molecules, is prepared through a novel semipinacol rearrangement utilizing a cyclic phosphorane or sulfite intermediate. The rearrangement proceeds with exclusive N-acyl group migration of a β-lactam ring and results in carbonyl functionality at the 7- and bridging 8-position of the bicycle. Precursor ring-fused β-lactam diols are prepared through a sequence of 4-exo trig carbamoyl radical cyclization, regioselective dithiocarbamate group elimination, and dihydroxylation.
authors.affiliation: School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. r.s.grainger@bham.ac.uk
authors.forename: Richard S
authors.initials: RS
authors.lastname: Grainger
authors.forename: Marie
authors.initials: M
authors.lastname: Betou
authors.forename: Louise
authors.initials: L
authors.lastname: Male
authors.forename: Mateusz B
authors.initials: MB
authors.lastname: Pitak
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Coles
mesh_terms: D000438:Alcohols / Q000138:chemical synthesis* / Q000737:chemistry; D053961:Azabicyclo Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D015394:Molecular Structure; D013237:Stereoisomerism; D047090:beta-Lactams / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000438:Alcohols; D053961:Azabicyclo Compounds; D047090:beta-Lactams