O-Methyl-N-nitroisourea as a NCO Surrogate in Cu-Catalyzed Alkane C–H Amidination. A Masked Isocyanate Strategy

The Cu-catalyzed C–H activation of alkanes in the presence of O-methyl-N-nitroisourea allows a facile entry to O-methyl-N-alkylnitroisoureas, which are shelf-stable isocyanate precursors. The latter are then readily converted into carbamates and ureas via an uncommon chloride-mediated demethylation process. O-Methyl-N-nitroisourea is available in two steps and on a large scale from urea and constitutes an easy to handle NCO surrogate. The methodology has also been applied to the synthesis of a methylisocyanate (MIC) precursor, a valuable synthon for pharmaceutical and agrochemical purposes and for the postfunctionalization of polyolefins.