An efficient macrolactonization procedure using a polymer bound carbodiimid
e is described. The procedure uses the polymer supported reagent as a repla
cement for dicyclohexylcarbodiimide and thus considerably simplifies the wo
rkup for such reactions. Partitioning between macrolactone and diolide is s
hown to depend upon the equivalents of reagent used in cases for which lact
onization is difficult. (C) 2000 Published by Elsevier Science Ltd.