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We aim to detect methylamine, CH$_{3}$NH$_{2}$, in a variety of hot cores anduse it as a test for the importance of photon-induced chemistry in ice mantlesand mobility of radicals. Specifically, CH$_3$NH$_2$ cannot be formed from atomaddition to CO whereas other NH$_2$-containing molecules such as formamide,NH$_2$CHO, can. Submillimeter spectra of several massive hot core regions weretaken with the James Clerk Maxwell Telescope. Abundances are determined withthe rotational diagram method where possible. Methylamine is not detected,giving upper limit column densities between 1.9 $-$ 6.4 $\times$ 10$^{16}$cm$^{-2}$ for source sizes corresponding to the 100 K envelope radius. Combinedwith previously obtained JCMT data analyzed in the same way, abundance ratiosof CH$_{3}$NH$_{2}$, NH$_{2}$CHO and CH$_{3}$CN with respect to each other andto CH$_{3}$OH are determined. These ratios are compared with Sagittarius B2observations, where all species are detected, and to hot core models. Theobserved ratios suggest that both methylamine and formamide are overproduced byup to an order of magnitude in hot core models. Acetonitrile is howeverunderproduced. The proposed chemical schemes leading to these molecules arediscussed and reactions that need further laboratory studies are identified.The upper limits obtained in this paper can be used to guide futureobservations, especially with ALMA.

Search for methylamine in high mass hot cores