Amides methyl, from isocyanates

Very recently a rapid method for the preparation of effective polymer-supported isocyanate resins has been reported [31]. Gel-type isocyanate resins tvere generated from aminomethyl resins and inexpensive substrates as alternatives to the commercially available, expensive macroporous polystyrene isocyanate supports. Several isocyanates have been investigated phenyl diisocyanate (PDI) tvas found to be the most efficient. Aminomethyl resin was pre-swollen in NMP, mixed with 2 equiv. PDI, and irradiated at 100 °C for 5 min (Scheme 16.7). Filtration, washing with NMP and DCM and drying under vacuum furnished the corresponding isocyanate resin. The reactivity of this novel gel-type resin was better than that of commercially available methyl isocyanate resins and it was successfully used for purification of a small amide library [31]. 

More than 100 years ago, Hofmaim reported in a series of papers the conversion of primary amides to amines with bromine in aqueous sodium hydroxide. The occasional side reaction leading to nitrile formation was also observed by Hofmann. Another early observed side reaction is the formation of ureas from the combination of isocyanate with unreacted amide. This particular side reaction can be circumvented by employing sodium methoxide in place of sodium hydroxide to afford the corresponding methyl carbamate, which upon distillation from calcium hydroxide affords the corresponding primary amine, as first described by Jeffreys. ... 

Lastly, mention will be made of two further amide block copolymer syntheses not mentioned above. The first employs living polymer anions from styrene, isoprene or methyl methacrylate to initiate the polymerization of isocyanates to diblock polymers containing nylon 1 sequences. In this approach, selective polymerization can be achieved at the unhindered isocyanate group of diisocyanates such as tolylene 2,4-diisocyanate to give products with pendant NCO groups (32) which are crosslinkable with diols to give tough resins. 

---