Rhazinilam synthesis iminium intermediate

In 2001, Magnus and co-workers reported a straightforward synthesis of racemic rhazinilam by initial construction of the pyrrole ring from a piperidone, Fig. (33) [154]. The sequential alkylation of piperidone 155 with iodoethane and allyl bromide furnished piperidone 156, having the requisite C-20 substitution of rhazinilam. After formation of the thiophenyl iminoether 157, A-alkylation with allyl bromide 158 furnished the corresponding iminium intermediate which underwent 1,5-... 

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