Oxabicyclo[3.2.1]octenes in organic synthesis: direct ring opening of oxabicyclo[3.2.1] ring systems with diisobutylaluminum hydride and a silyl ketene acetal--synthesis of the chiral C(19)-C(26) and C(27)-C(32) fragments of Scytophycin C.
[reaction: see text] An efficient strategy for transforming meso-oxabicyclo[3.2.1]octenone 1 into optically active intermediates for macrolide synthesis has been developed. The direct bridgehead opening of optically active oxabicyclo[3.2.1]octene derivative 2 with hydride or a silyl ketene acetal utilizing the highly polar medium lithium perchlorate in diethyl ether resulted in highly functionalized cycloheptenones, which were transformed into the C(19)-C(26) and C(27)-C(32) fragments of Scytophycin C.
Hunt
Kevin W
KW
Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA.
Grieco
Paul A
PA
D000080:Acetals / Q000737:chemistry; D000970:Antineoplastic Agents / Q000138:chemical synthesis*; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000138:chemical synthesis* / Q000737:chemistry*; D005030:Ethylenes / Q000737:chemistry; D007659:Ketones / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry; D011714:Pyrans / Q000138:chemical synthesis*
D000080:Acetals; D000970:Antineoplastic Agents; D019086:Bridged Bicyclo Compounds, Heterocyclic; D005030:Ethylenes; D007659:Ketones; D009942:Organometallic Compounds; D011714:Pyrans; C449042:scytophycin C; C035719:diisobutylaluminum; C008223:ketene