O-Methyl-N-Nitroisourea as a NCO Surrogate in Cu-Catalyzed Alkane C-H isocyanation. A Masked Isocyanate Strategy.

The Cu-catalyzed C-H activation of alkanes in the presence of O-methyl-N-nitroisourea affords a facile entry to O-methyl-N-alkylnitroisoureas, shelf stable and benign isocyanate precursors. The latter is then readily converted into carbamates and ureas via an uncommon chloride-mediated demethylation process. O-methyl-N-nitroisourea is available in two steps and 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 post-functionalization of a low density polyethylene.