117970-38-4

Upstream product

• 121643-36-5 2-Bromo-6-diisopropylamino-1-azafulvene 
• 882-33-7 diphenyldisulfane 
• 79600-35-4 2-(phenylsulfenyl)pyrrole 
• 68-12-2 N,N-dimethyl-formamide 
• 64435-30-9 N⁵,N⁵,N¹⁰,N¹⁰-tetramethyl-5,10-dihydrodipyrrolo[1,2-a:1',2'-d]pyrazine-5,10-diamine 

Downstream Products

• 1173245-21-0 5-(phenylsulfinyl)pyrrole-2-carboxaldehyde 
• 222972-61-4 5-benzenesulfonyl-1-methyl-1H-pyrrole-2-carbaldehyde 
• 222972-59-0 5-benzenesulfonyl-1H-pyrrole-2-carbaldehyde 

Relevant academic research and scientific papers

Access to indoles via Diels-Alder reactions of 5-methylthio-2-vinylpyrroles with maleimides

Diels-Alder reactions of 5-methylthio-2-vinyl-1H-pyrroles with maleimides followed by isomerization gave tetrahydroindoles in moderate to good yield. Aromatization using activated MnO2 in refluxing toluene gave the corresponding 2-methylthioindoles in good yields, and demethylthioation using Raney nickel gave the 2-H indoles in excellent yields. The protection of the adducts produced aromatization in improved yield, demonstrating the effectiveness of the methylthio group as a protecting group for pyrroles; however, 5-methylthio-2-vinylpyrrole was shown to perform with slightly less efficiency than 2-vinylpyrrole in Diels-Alder reactions, indicating the protective group was more deactivating than desired. This route toward indoles offers high convergency and conveniently available starting materials that are easily purified. Bis-methylthioated vinylpyrroles were shown to have potential as highly activated Diels-Alder dienes.

Asymmetric oxidation of 2-(arylsulfenyl)pyrroles

The asymmetric oxidation of prochiral 2-(arylsulfenyl)pyrroles has been investigated. A marked electronic effect within the substrate significantly influenced the degree of enantioselectivitv obtained, with very high enantio-selectivity being obtained for

Comparison of benzene, nitrobenzene, and dinitrobenzene 2-arylsulfenylpyrroles

(Chemical Equation Presented) The effectiveness of the 2,4- dinitrobenzenesulfenyl and 4-nitrobenzenesulfenyl groups as masking and directing groups at the 2-position of pyrrole has been investigated and compared to that of 2-phenylthiopyrrole. The presen

Synthesis of 5-substituted pyrrole-2-carboxaldehydes. Part I. Generation of formal 5-lithiopyrrole-2-carboxaldehyde equivalents by bromine-lithium exchange of 2-bromo-6-(diisopropylamino)-1-azafulvene derivatives

The first known lithiated 1-azafulvene derivatives, e.g., 8 and 13a, were generated by a low-temperature bromine-lithium exchange procedure with tert-butyllithium.These lithio species show substantial stability at /=-90 deg C because, at these temperatures, the sterically demanding 6-diisopropylamino moiety, unlike the dimethylamino group, completely inhibits nucleophilic addition to C-6.At higher temperatures, the addition of tert-butyllithium to C-6 is significant and it can become the dominant process.The lithio species 8 is a useful formal equivalent of 5-lithiopyrrole-2-carboxaldehyde since, on reaction with electrophilic reagents and subsequent hydrolysis, a wide variety of regiochemically pure 5-substituted pyrrole-2-carboxaldehydes is formed.The 6-dialkylamino-1-azafulvenes described herein exist predominantly or exclusively as the syn conformer in solution at room temperature.This conformational preference is confirmed by a significance NOE effect between H-4 and H-6 in the parent diisopropylamino compound 3f.The origin of the syn conformational preference stems from a substantial contribution of the charge-separated form 16 to the ground state structure of these compounds, a phenomenon that is strongly supported by variable temperature NMR measurements on 2-bromo-6-diisopropylamino-1-azafulvene (3c).Key words: 2-bromo-6-diisopropylamino-1-azafulvenes, stereochemistry, lithiation, pyrolle-2-carboxaldehydes.

216. Lithiated Azafulvenes by Halogen/Metal Interchange of Brominated 6-(Diisopropylamino)-1-azafulvene Derivatives. Novel Synthesis of 5-Mono- and 4,5-Disubstituted 1H-Pyrrole-2-carbaldehydes

The first known lithiated 1-azafulvene derivatives were generated by low-temperature halogen/metal interchange, with t-BuLi, from the corresponding brominated 6-diisopropylamino compounds 3b and 12.These Li species reacted with sundry electrophilic reagents to give products which, on the basic hydrolysis, were converted into 5-mono- or 4,5-disubstituted pyrrole-2-carbaldehydes 10 and 16, respectively.

LITHIATION OF THE 6-DIMETHYLAMINO-1-AZAFULVENE DIMER. A VERSATILE SYNTHESIS OF 5-SUBSTITUTED PYRROLE-2-CARBOXALDEHYDES.

Metalation of the dimer 1 of 6-dimethylamino-1-azafulvene, with t-butyllithium at -15 deg C, gave the 3,8-dilithio derivate 2, which after reaction with diverse electrophilic reagents and hydrolysis, provided a wide variety of 5-substituted pyrrole-2-carboxaldehydes 5.