Room temperature acetalization of aldehydes with methanol has been carried out using metalorganicframeworks (MOFs) as solid heterogeneous catalysts. Of the MOFs tested, a copper-containing MOF [Cu3(BTC)2] (BTC=1,3,5-benzenetricarboxylate) showed better catalytic activity than an iron-containing MOF [Fe(BTC)] and an aluminium containing MOF [Al2(BDC)3] (BDC=1,4-benzenedicarboxylate). The protocol