Synthesis of the hydroazulene ring system of guanacastepene.
[reaction: see text] A 12-step synthesis of 26, the functionalized hydroazulenone ring of guanacastepene (1), has been completed using the EtAlCl(2)-initiated cyclization of gamma,delta-unsaturated ketone 13 to construct 2,2,3-trisubstituted cyclopentanone 14, the palladium-catalyzed coupling of vinylmagnesium bromide with enol triflate 17 to prepare triene 21, and olefin metathesis of triene 21 to form the key hydroazulene 20.
Snider
B B
BB
Department of Chemistry MS015, Brandeis University, Waltham, Massachusetts 02454-9110, USA. snider@brandeis.edu
Hawryluk
N A
NA
D000475:Alkenes / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D003508:Cycloheptanes / Q000138:chemical synthesis* / Q000737:chemistry; D004224:Diterpenes / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry
D000475:Alkenes; D000900:Anti-Bacterial Agents; D003508:Cycloheptanes; D004224:Diterpenes; D007659:Ketones; C409194:guanacastepene; D010165:Palladium