The origins of different stereoselectivities observed experimentally in the alkylations of azulenone precursors in the guanacastepene A synthesis have been determined through density functional theory investigations. The optimized transition structures of methylation of two different guanacastepene A precursors show that steric effects, rather than torsional factors that often determine such stereoselectivities, dictate the preferred products observed.
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| http://dx.doi.org/10.1021/jo902283a | DOI Listing |
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