2199-55-5Relevant academic research and scientific papers
A direct preparation of N-unsubstituted pyrrole-2,5-dicarboxylates from 2-Azidocarboxylic esters
Ciez, Dariusz
supporting information; experimental part, p. 4282 - 4285 (2010/01/16)
A new and easy method for synthesis of symmetric pyrrole-2,5-dlcarboxylate derivatives via a simple tltanium(IV)-medlated oxidative dimerlzation of 2-azldocarboxyllc esters is described. The process involves a transformation of tltanium(IV) enolates into
ELECTROPHILIC HETEROAROMATIC SUBSTITUTIONS. X. UNEXPECTED RESULTS IN THE α-SIDE-CHAIN CHLORINATION OF A SERIES OF ETHYL 3,4,5-TRIALKYLPYRROLE-2-CARBOXYLATES
Scarsella, Marco,Sleiter, Giancarlo
, p. 757 - 762 (2007/10/02)
The reaction of a series of 3,4,5-trialkyl-substituted ethyl pyrrole-2-carboxylates with an excess of sulphuryl chloride followed by solvolysis has been investigated in several solvents and under different experimental conditions.In all cases, beside the expected α-side-chain substituted product, substantial amounts of derivatives functionalised also in a β-side chain have been isolated and identified.The process turned out to be electrophilic in nature and to involve allylic migration of the halogen from the α-sigma adduct to the adjacent β-side chain.Virtually identical results have been obtained when elemental chlorine was used.
Alkylation process
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, (2008/06/13)
Substituted pyrrole compounds, such as 3-ethyl-4-methyl-5-carbethoxy pyrrole, 2,4-dimethyl-3-acetyl pyrrole and 2-methyl-5-carboxy pyrrole-4-propionic acid diethyl ester, are alkylated in a single step by reaction with an aldehyde or ketone in the presence of both an acid condensing agent such as hydriodic acid and a compatible reducing agent such as metallic zinc or stannous chloride. Suitable carbonyl reactants include formaldehyde, paraldehyde, isobutyraldehyde, acetone, cyclohexanone and methyl-isobutyl ketone. This application is a continuation application of U.S. application Ser. No. 281,624 filed Aug. 18, 1972, now abandoned, which is a continuation-in-part application of U.S. application Ser. No. 832,001, filed June 10, 1969, now abandoned.
