The reaction 5-benzylidene-2, 3, 4, 5-tetrahydropyridine (1) with nucleophilic reagents, such as sodium tetrahydroborate, lithium tetrahydridoaluminate, organometallic reagents, pyrrole, or ethyl propiolate, has been studied. The reaction of 1 with sodium tetrahydroborate, lithium tetrahydridoaluminate, phenylmagnesium bromide, butyllithium gave exclusively respective 1, 2-adducts. The reaction with pyrrole gave a tricyclic 1: 1 adduct while 1 formed a 1: 2 ...