Reaction of methyl diazoacetate with aldehydes, amines, thiols, alcohols and acids over transition metal-exchanged clays

Metal-exchanged clays (M=Rh and Cu) catalyze effectively the reaction of me thyl diazoacetate with various aldehydes, affording the corresponding beta- keto esters in high yields. They have also been effective in the decomposit ion of methyl diazoacetate to form metallocarbenes which, in turn, successf ully insert into X-H (X=N, O, S, CO2) bonds of a variety of amines, aldehyd es, thiols and acids, thereby producing the corresponding esters.