Oxalic acld as a catalyst for efficient synthesis of bis-(indolyl)methanes,and 14-aryl-14H-dibenzo[a

A simple,efficient,and environment benign route was developed for the preparation of bis-(indolyl)methanes and 14-aryl-14H-dibenzo[a,j]xanthenes from condensation of various aromatic aldehydes or ketones with indole,and 2-naphthol,respectively,using oxalic acid catalyst in aqueous medium.Use of cheap and easily available catalyst,better yields and simple reaction protocol are the advantages of the present method.