98943-79-4

Upstream product

• 613-31-0 9,10-dihydroanthracene 
• 98943-68-1 2,2-dimethyl-1-(4-phenylbenzoyl)aziridine 

Relevant academic research and scientific papers

Three positional isomers of substituted triphenylmethanes from reactions of trityl anion with 1-acyl-2,2-dimethylaziridines

Ring opening of aziridines 4a-d in reactions with trityl anion Tr(-) proceeds exclusively by cleavage of the NCMe2 bond.Substitution of the benzylic carbon of Tr(-) leads to 'central' products 10a-d in yields of 0-5percent.This is ascribed to an SN2 reaction with borderline character, as is well known from reactions of aziridines 4a-d with other nucleophiles.All remaining ring-opening reactions result from single-electron transfer (SET).This is direct SET from Tr(-) to aziridines 4a-c.For compound 4d (acyl = cinnamoyl), the SET reaction is of the innersphere type and proceeds via Michael addition, at least in part.Homolytic ring opening of the generated aziridino ketyls 5 forms the tertiary amidatoalkyl radicals 6.Main reaction of radicals 6a-c is transfer of a hydrogen atom from one of its two methyl groups to the generated trityl radical Tr..Methallylamides 7 and enamides 8 are the final products. ortho-Substituted triphenylmethanes 12 and/or its olefinic precursors 13 arise in ca. 20percent yield.A mechanism for the formation of these unique products is proposed that first converts the radicals 6 into the corresponding carbanions 16 which undergo an SN2' reaction with one allylic system TrCHCH=CH* of the dimer 14 of Tr..The leaving group Tr(-) is eliminated from this partial structure when carbanions 16 attack the marked carbon converting it finally into the substituted ortho carbon of compounds 12.Addition of radicals 6 to Tr(-) is probably the way to the para-substituted triphenylmethanes 11, which arise in yields of only 0-1percent from aziridines 4a,b (acyl = benzoyl, pivaloyl).Higher yields of para-substituted compounds 11 are obtained from aziridines 4c (acyl = 4-phenylbenzoyl) and 4d.This is ascribed, at least for substrate 4c, to a chain reaction because ketyl 5c must be formed more rapidly than ketyls 5a,b.A substantial part of radical 6d cyclizes, ending up as the triphenylmethane compound 26 that carries a pyrrolidone ring in the para position.

Radical Combination in the ortho Position of Trityl Radical Observed in Single-electron Transfer Reactions of Trityl Anion

Single-electron transfer reactions between trityl anion and 1-acyl-2,2-dimethylaziridines provide, among other products, the methallyl amides 7 and the triphenylmethanes 8 carrying an amidoethyl chain attached with the tertiary carbon ortho to the triphen

Highly Regioselective Ring Cleavage of N-Acylaziridines by "Anthracene Hydride" (Anion of 9,10-Dihydroanthracene). Intermediacy of a Carbonyl Adduct. Influence of Nitrogen Inversion on the Ring Opening?

Anthracene hydride AH- reacts with N-acylaziridines by reductive opening of the aziridine ring and/or amidoethylation of AH-.When the two aziridine carbons are differently substituted, in both reactions only that bond is broken which can form the more stable carbon radical quite in accord with the intermediacy of a radical anion (ketyl) 14 and with the known homolytic cleavage of 14 forming the radical 15.The extra electron in 14 is provided by AH- being oxidized to the radical AH., which can react with 15 either by radical combination or by hydrogen transfer.The reaction of AH- with N-aroylaziridines can be interrupted at the stage of the carbonyl adduct 5 as is shown by the isolation of the ketones 7a,b.So, 5 (R4 = aryl) is considered to be in equilibrium with the radical pair AH./14.The conversion of 5 into the final products progresses as expected from its structure apart from the observed retardation by a phenyl substituent in the aziridine ring (3a, 4a).This retardation is tentatively explained by a hypothesis assuming ring opening of 14 to occur in the transition state of nitrogen inversion.The anion X- of xanthene resembles AH- in its reactivity.Both carbanions react with N-sulfonylaziridines as expected from an SN2 mechanism.