73633-57-5

Upstream product

• 636-41-9 2-methyl-1H-pyrrole 
• 100-44-7 benzyl chloride 
• 32776-14-0 1-phenyl-hexane-2,5-dione 
• 1319727-30-4 2-benzyl-2-[(3,4-dimethoxybenzylidene)amino]-5-oxohexanenitrile 
• 1319727-31-5 2-benzyl-5-methyl-3,4-dihydro-2H-pyrrole-2-carbonitrile 
• 698389-24-1 C₁₈H₁₈N₂O₂ 
• 1795-98-8 rac-phenylalaninol 
• 67-63-0 isopropyl alcohol 
• 1271-66-5 dimethyltitanocene 
• 25543-13-9 N-methyloxycarbonylsuccinimide 
• 121643-34-3 N,N-Diisopropylpyrrole-2-formiminium chloride 
• 72155-45-4 Boc-L-phenylalaninal 
• 180516-67-0 tert-butyl 2-benzyl-5-methyl-1H-pyrrole-1-carboxylate 
• 121643-36-5 2-Bromo-6-diisopropylamino-1-azafulvene 

Relevant academic research and scientific papers

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.

A convenient one-pot synthesis of polysubstituted pyrroles from N-protected succinimides

The dienamine products formed by the reaction between polysubstituted succinimides and the Petasis reagent were subjected to isomerization under mild acidic conditions to give polysubstituted pyrroles in excellent yields (85-95%). The scope and limitations of this methodology are explored.

A sustainable catalytic pyrrole synthesis

The pyrrole heterocycle is a prominent chemical motif and is found widely in natural products, drugs, catalysts and advanced materials. Here we introduce a sustainable iridium-catalysed pyrrole synthesis in which secondary alcohols and amino alcohols are deoxygenated and linked selectively via the formation of C-N and C-C bonds. Two equivalents of hydrogen gas are eliminated in the course of the reaction, and alcohols based entirely on renewable resources can be used as starting materials. The catalytic synthesis protocol tolerates a large variety of functional groups, which includes olefins, chlorides, bromides, organometallic moieties, amines and hydroxyl groups. We have developed a catalyst that operates efficiently under mild conditions.

Pyrroles and indolizidines from deprotonated α-(alkylideneamino) nitriles

Their ready availability from simple starting materials in only two synthetic steps and their versatility as building blocks for the construction of highly substituted amines and N-heterocycles renders α-(alkylideneamino) nitriles useful synthetic intermediates. Herein, short syntheses of tri- and tetrasubstituted pyrroles including the northern half of the HMG-CoA reductase inhibitor atorvastatin as well as an access to 3-substituted indolizidines will be described. Georg Thieme Verlag Stuttgart - New York.

Pd(0)-Catalyzed Conjugate Addition of Benzylzinc Chlorides to α,β-Enones in An Atmosphere of Carbon Monoxide: Preparation of 1,4-Diketones

Pd(0)-catalyzed conjugate addition of benzylzine chloride to methyl vinyl ketone in the presence of chlorotrimethylsilane and lithium chloride in an atmosphere of carbon monoxide at room temperature afforded 1-phenyl-2,5-hexanedione monosilyl enol ether. In this catalytic carbonylation, four components are connected in one reaction. Successive acidic workup generated a variety of 1,4-diketones from substituted benzylzine chlorides or related compounds and α,β-enones. Some products were converted to cyclopentenones or five-membered heterocyclic compounds containing an N, O, or S atom.

Nitrogen fixation: Synthesis of heterocycles using molecular nitrogen as a nitrogen source

Nitrogen fixation using transition metals is a fascinating process. We have already reported on the incorporation of molecular nitrogen into organic compounds using a titanium-nitrogen complex reported by Yamamoto. We developed a novel titanium-catalyzed nitrogenation procedure using TiCl4 in the presence of an excess amount of Li and TMSCl. In this reaction, a 1 atm pressure of nitrogen gas can be used and the reaction proceeds at room temperature. The procedure is very simple. A THF solution of TiCl4 or Ti(O iPr)4 (1 equiv.), Li (10 equiv.), and TMSCl (10 equiv.) was stirred under an atmosphere of nitrogen at room temperature overnight to give titanium-nitrogen complexes. Although the structures of the titanium-nitrogen complexes have not yet been determined, they would consist of N(TMS)3, X2TiN(TMS)2, and XTi=NTMS. Using this procedure, various heterocycles, such as indole, quinoline, pyrrole, pyrrolizine, and indolizine derivatives, could be synthesized from molecular nitrogen in good-to-moderate yields as a stoichiometric reaction based on a titanium complex by a one-pot reaction. Furthermore, monomorine I and pumiliotoxin C were synthesized from molecular nitrogen as a nitrogen source. This procedure was further extended for the syntheses of heterocycles using a catalytic amount of titanium complex; also, indole and pyrrole derivatives were obtained in high yields.

Synthesis of Dihydropyrrole and Pyrrole Derivatives by Radical Cyclization of γ,δUnsaturated Ketone O-Acetyloximes

Treatment of γδ-unsaturated ketone O-acetyloximes with a catalytic amount of 1,5-naphthalenediol or hydroquinone, acetic acid, and 1,4-cyclohexadiene affords various dihydropyrrole and pyrrole derivatives via radical cyclization induced by one-electron reduction of the oximes.

A general synthesis of pyrroles and fused pyrrole systems from ketones and amino acids

The lithium enolates of ketones react with BOC-α-amino aldehydes and BOC-α-amino ketones to afford aldol intermediates that cyclize under acidic conditions to yield pyrroles. The BOC-amino aldehydes and ketones are readily available from α-amino acids. The method allows incorporation of a wide variety of substituents at any of the five atoms of the pyrrole ring and is also suitable for the preparation of fused pyrrole systems.

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.