Tris(pentafluorophenyl)borane was used as a new catalyst in the formation of P-B bonds by dehydrocoupling of phosphine-boranes.

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ABSTRACT:The ring enlargement

Esters of proteinogenic amino acids efficiently catalyse the formation of erythrose and threose under aqueous conditions in the highest yields and enantioselectivities yet reported. Remarkably while esters of (L)-proline yield (L)-carbohydrates, esters of (L)-leucine and (L)-alanine generate (D)-carbohydrates, offering the potential to account for the prebiotic link between natural (L)-amino acids and natural (D)-sugars.

Esters of proteinogenic amino acids efficiently catalyse the formation of erythrose and threose under potentially prebiotic conditions in the highest yields and enantioselectivities yet reported. Remarkably while esters of (L)-proline yield (L)-tetroses, esters of (L)-leucine, (L)-alanine and (L)-valine generate (D)-tetroses, offering the potential to account for the link between natural (L)-amino acids and natural (D)-sugars. The effect of pH and NaCl on the yields and enantioselectivities was also investigated and was shown to be significant, with the optimal enantioselectivities occurring at pH 7.