Dehydrations of aldoximes into isonitriles or nitriles by means of rnethylketene diethylacetal have been studied. ilddition compounds of aromatic-syn-aldoxime5 and methylketene diethylacetal decompose, in the presence of a catalytic amount of boron trifluoride and mercuric oxide, into corresponding isonitriles in good yields. On the other hand, adducts of methylketene diethylacetal and aromatic-anti-aldoximes, as we11 as of methylketene ...