title: Facile synthesis of 11-carboxamido-androst-4,9(11)-dienes via palladium-catalyzed aminocarbonylation.
abstract: 11-Carboxamido-androst-4,9(11)-dienes were synthesized from the corresponding 11-iodo-androst-4,9(11)-diene derivative in palladium-catalyzed aminocarbonylation reaction under mild reaction conditions. The synthesis of the iodo-alkene substrate is based on the transformation of the 11-keto derivative to hydrazone, which was treated with iodine in the presence of a base (1,1,3,3-tetramethyl guanidine). The 11-carboxamides were synthesized in moderate to high isolated yields by using simple alkyl/arylamines or amino acid methylesters as N-nucleophiles. The highly active palladium catalysts enable the homogeneous catalytic functionalization at one of the most hindered position (C-11) of the steroidal skeleton.
authors.affiliation: University of Pécs, Department of Inorganic Chemistry, Ifjúság u. 6., H-7624 Pécs, Hungary.
authors.forename: Péter
authors.initials: P
authors.lastname: Acs
authors.forename: Balázs
authors.initials: B
authors.lastname: Jakab
authors.forename: Attila
authors.initials: A
authors.lastname: Takács
authors.forename: László
authors.initials: L
authors.lastname: Kollár
mesh_terms: D000475:Alkenes; D000730:Androstadienes / Q000138:chemical synthesis* / Q000737:chemistry; D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D008968:Molecular Conformation; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D011090:Polyenes / Q000138:chemical synthesis* / Q000737:chemistry; D013256:Steroids / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000475:Alkenes; D000730:Androstadienes; D011090:Polyenes; D013256:Steroids; D010165:Palladium; D002244:Carbon