Cobalt-mediated (2 + 2 + 2) cycloadditions en route to natural products: a novel total synthesis of steroids via the one-step construction of the B,C,D framework from an A-ring precursor

Journal Article · Fri Aug 27 00:00:00 EDT 1982 · J. Org. Chem.; (United States)

DOI:https://doi.org/10.1021/jo00139a012· OSTI ID:6863033

Sternberg, E D; Vollhardt, K P.C.

The first application of the cobalt-mediated intramolecular cyclization of ..cap alpha..,delta,..omega..-diynenes to annulated cyclohexadienes in natural product synthesis is described by demonstrating its feasibility in a versatile and efficient steroid synthesis, including a new total synthesis of the Torgov intermediate, 3-methoxyestra-1,3,5(10),8,14-pentaen-17-one, via a new steroid, 3-methoxyestra-1,3,5(10),8(14),9-pentaen-17-one ethylene ketal. Several model reactions en route to B-homo-7-oxa steroids allow the delineation of some stereochemical details of the transition-metal-catalyzed (2 + 2 + 2) cycloaddition reaction.

• Research Organization: Univ. of California, Berkeley
• OSTI ID: 6863033
• Journal Information: J. Org. Chem.; (United States), Journal Name: J. Org. Chem.; (United States) Vol. 47:18; ISSN JOCEA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ALKENES
CHEMICAL PREPARATION
CHEMICAL REACTION KINETICS
COBALT
CYCLOALKENES
DIENES
ELEMENTS
HYDROCARBONS
KINETICS
METALS
ORGANIC COMPOUNDS
POLYENES
REACTION KINETICS
STEREOCHEMISTRY
STEROIDS
SYNTHESIS
TRANSITION ELEMENTS