Oxabicyclo[3.2.1]octenes in Organic SynthesisDirect Ring Opening of Oxabicyclo[3.2.1] Systems Employing Silyl Ketene Acetals in Concentrated Solutions of Lithium Perchlorate−Diethyl Ether: Application to the Synthesis of the C(19)−C(27) Fragment of Rifamycin S
摘要:
[GRAPHICS]The direct opening at the bridgehead of oxabicyclo[3.2.1]octenes employing silyl ketene acetals in 4.0-5.0 M lithium perchlorate in diethyl ether has been realized, which gives rise to highly functionalized cycloheptadienes that can be further manipulated for use in natural product synthesis. The bridgehead opening reaction has been employed in the construction of the C(19)-C(27) fragment of Rifamycin S.
Oxabicyclo[3.2.1]octenes in Organic SynthesisDirect Ring Opening of Oxabicyclo[3.2.1] Systems Employing Silyl Ketene Acetals in Concentrated Solutions of Lithium Perchlorate−Diethyl Ether: Application to the Synthesis of the C(19)−C(27) Fragment of Rifamycin S
摘要:
[GRAPHICS]The direct opening at the bridgehead of oxabicyclo[3.2.1]octenes employing silyl ketene acetals in 4.0-5.0 M lithium perchlorate in diethyl ether has been realized, which gives rise to highly functionalized cycloheptadienes that can be further manipulated for use in natural product synthesis. The bridgehead opening reaction has been employed in the construction of the C(19)-C(27) fragment of Rifamycin S.
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 AcetalSynthesis of the Chiral C(19)−C(26) and C(27)−C(32) Fragments of Scytophycin C
作者:Kevin W. Hunt、Paul A. Grieco
DOI:10.1021/ol010253c
日期:2002.1.1
GRAPHICSAn 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.
Oxabicyclo[3.2.1]octenes in Organic SynthesisDirect Ring Opening of Oxabicyclo[3.2.1] Systems Employing Silyl Ketene Acetals in Concentrated Solutions of Lithium Perchlorate−Diethyl Ether: Application to the Synthesis of the C(19)−C(27) Fragment of Rifamycin S
作者:Kevin W. Hunt、Paul A. Grieco
DOI:10.1021/ol0003836
日期:2001.2.1
[GRAPHICS]The direct opening at the bridgehead of oxabicyclo[3.2.1]octenes employing silyl ketene acetals in 4.0-5.0 M lithium perchlorate in diethyl ether has been realized, which gives rise to highly functionalized cycloheptadienes that can be further manipulated for use in natural product synthesis. The bridgehead opening reaction has been employed in the construction of the C(19)-C(27) fragment of Rifamycin S.