Palladium® complexes carbonylation, natural products synthesis

Section 2.5). In contrast, the unprotected diol 6.84 gave a mixture of products, including a bis-carbonylation product 6.86. The diol 6.84 could, however, be cyclized directly to diospongin A 6.83 by treatment with a stoichiometric amount of a palladium(II) complex and a phenyl tin reagent. Another synthesis of this natural product may be found in Scheme 8.93. 

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