The hydrcifluoroborate salts of 2-acyl-1,2-dihydroisoquinaldonitriles (Reissert compounds) undergo reactions with alkenes to give substituted 2-(l-isoquinolyl)pyrroles and with alkynes to give substituted pyrrolo[2,1-a]isoquinolines. T o expand the scope and synthetic usefulness of these reactions, a wide variety of Reissert salts, alkenes, and alkynes, respectively, have been utilized. The reactions are general in nature. They take place successfully when the acyl group of the Reissert compound is varied from a simple aliphatic one (N-acetyl, for example) to a sterically hindered aromatic one [N-(1 -naphthoyl)]. The olefin reactions take place with monosubstituted ethylenes (styrene) and with 1,2-disubstituted ethylenes (trans-stilbene). Also, the reactions occur when either electronwithdrawing (as in diethyl maleate) or electron-donating [as in 1-(3,4-dimethoxyphenyl)propene] substituents are bonded to the ethylene moiety. With regard to the alkyne reactions, wide variations in either the Reissert salt or the alkynes are also consonant with successful reactions.Evidence has been presented t h a t solutions of the hydrofluoroborate salts of 2-acyl-l,2-dihydroisoquinaldonitriles (Reissert compounds*) consist of equilibrium mixtures of 1, 3, and 4, the latter being the major ~o m p o n e n t .~.~ These salts 1 f l 2 3 4are also presumed to be in equilibrium with the original Reissert compound, the 1,3-dipolar compound 2 ( a mesoionic compound), and fluoroboric acid. Several studies of 1,3-dipolar addition reactions of hydrofluoroborate salts of Reissert compounds have been Numerous examples of complex, acid-catalyzed condensation-rearrangement reactions of Reissert compounds with olefins have also been re-I t is believed t h a t these condensation-rearrangement reactions involve an initial Diels-Alder type of cycloaddition of the olefin to the isomeric form 4 of the Reissert salt, and detailed mechanisms of reaction have been suggested.'lJ* In order to expand the scope and synthetic usefulness of these reactions, we have now carried out reactions of a variety of Reissert hydrofluoroborate salts with a variety of olefinic and acetylenic compounds. T h e results of the reactions with olefinic compounds are summarized in Table I, and those with acetylenic compounds in Table 11. I t is clear that both types of reactions are general in nature. T h e reactions take place successfully when the acyl group of the Reissert compound is varied from a simple aliphatic one (N-acetyl, for example) t o a sterically hindered aromatic one [N-(1-naphthoyl)]. The olefin reactions take place with both monosubstituted ethylenes (styrene) and with 1,2-disubstituted ethylenes (stilbene). Also, the reactions occur when either electron-withdrawing (as in diethyl maleate) or electron-donating [as in 1-(3,4-dirnethoxyphenyl)propene] substituents are bonded to the ethylene moiety. I t is also clear from the data presented in Table I1 and in previous publication^^-^ that wide variation in the acetylenes is consonant with successful reactions.0...