The preparation of ester heterocycles mostly uses heteroatoms as nucleophilic sites, which are achieved by intramolecular substitution or addition reactions. Compound: 1-(tert-Butyl)-1H-pyrrole-2,5-dione( cas:4144-22-3 ) is researched.Reference of 1-(tert-Butyl)-1H-pyrrole-2,5-dione.Butler, Richard N.; Coyne, Anthony G.; McArdle, Patrick; Cunningham, Desmond; Burke, Luke A. published the article 《Regioselectivity and endo/exo selectivity in the cycloadditions of the phthalazinium dicyanomethanide 1,3-dipole with unsymmetrical alkene and alkyne dipolarophiles. Unexpected reversals of regiochemistry: a combined experimental and DFT theoretical study》 about this compound( cas:4144-22-3 ) in Journal of the Chemical Society, Perkin Transactions 1. Keywords: dipolar cycloaddition phthalazinium dicyanomethanide alkene alkyne regiochem stereochem. Let’s learn more about this compound (cas:4144-22-3).
In the reactions of phthalazinium dicyanomethanide 1,3-dipole with electron-poor monosubstituted alkene and alkyne dipolarophiles the dicyanomethanide terminus bonds to the unsubstituted carbon giving 1-substituted pyrrolo[2,1-a]phthalazines. With electron-rich dipolarophiles the regiochem. is reversed and the products are 2-substituted pyrrolo[2,1-a]phthalazines. An unexpected reversal of regiochem. occurred with Me methacrylate, due to a steric effect of the C-Me group, and the main product was 2-exo-methyl-2-endo-methoxycarbonyl-3,3-dicyano-1,2,3,10b-tetrahydropyrrolo[2,1-a]phthalazine, I. endo Cycloadditions were strongly favored with alkene dipolarophiles containing π bonds in substituents on the alkene unit. With N-substituted maleimides endo products were formed exclusively even when the N-substituent was tBu or adamantyl. Only with alkoxyvinyl ethers were exo-cycloadducts encountered. The mechanisms are discussed in conjunction with DFT calculations An X-ray crystal structure is reported on endo-N-tert-butyl-3,3-dicyano-1,2,3,10b-tetrahydropyrrolo[2,1-a]phthalazine-1,2-dicarboximide, II.
From this literature《Regioselectivity and endo/exo selectivity in the cycloadditions of the phthalazinium dicyanomethanide 1,3-dipole with unsymmetrical alkene and alkyne dipolarophiles. Unexpected reversals of regiochemistry: a combined experimental and DFT theoretical study》,we know some information about this compound(4144-22-3)Reference of 1-(tert-Butyl)-1H-pyrrole-2,5-dione, but this is not all information, there are many literatures related to this compound(4144-22-3).
Reference:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics