Zinc and Trimethylsilyl Chloride Mediated Synthesis of 2,3,5-Trisubstituted Pyrrole Diesters from Nitriles and Ethyl Bromoacetate

Rao, H. Surya Prakash; Desai, Avinash

doi:10.1055/s-0034-1380403

Cited by 22 publications

(2 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rao has shown that aliphatic, aromatic, and benzylic nitriles could be converted into 2,3,5-trisubstituted pyrrole diesters 164 via a zinc-mediated pseudo four-component reaction catalyzed by TMSCl (Scheme 18). 76 The reaction proceeds by the addition of the zinc enolate of ethyl bromoacetate 165 to the nitrile to form enamino ester 166. Then, C-alkylation with another molecule of ethyl bromoacetate produces diester 167, which undergoes Perkin ester condensation with another molecule of zinc enolate 165 to form key intermediate 168; subsequent dehydrative cyclization results in trisubstituted pyrroles 164.…”

Section: Scheme 18 From Cyanidesmentioning

confidence: 99%

Recent Advancements in Pyrrole Synthesis

Philkhana¹,

Badmus²,

Reis³

et al. 2021

Synthesis

View full text Add to dashboard Cite

This review article features selected examples on the synthesis of functionalized pyrroles that were reported between 2014 and 2019. Pyrrole is an important nitrogen-containing aromatic heterocycle that can be found in numerous compounds of biological and material significance. Given its vast importance, pyrrole continues to be an attractive target for the development of new synthetic reactions. The contents of this article are organized by the starting materials, which can be broadly classified into four different types: substrates bearing π-systems, substrates bearing carbonyl and other polar groups, and substrates bearing heterocyclic motifs. Brief discussions on plausible reaction mechanisms for most transformations are also presented.1 Introduction2 From π-Systems2.1 Alkenes2.2 1,6-Dienes2.3 Allenes2.4 Alkynes2.5 Propargylic Groups2.6 Homopropargylic Amines3 From Carbonyl Compounds3.1 Aldehydes3.2 Ketones3.3 Cyanides and Isocyanides3.4 Formamides3.5 β-Enamines3.6 Dicarbonyl Compounds4 From Polar Compounds4.1 Aminols4.2 Diols4.3 Organonitro Compounds5 From Heterocycles5.1 Münchnones5.2 Isoxazoles5.3 Carbohydrates5.4 trans-4-Hydroxy-l-prolines5.5 Pyrrolines6 Summary

show abstract

Section: Scheme 18 From Cyanidesmentioning

confidence: 99%

Recent Advancements in Pyrrole Synthesis

Philkhana¹,

Badmus²,

Reis³

et al. 2021

Synthesis

View full text Add to dashboard Cite

show abstract

“…181 A Blaise-type reaction gave a trisubstituted pyrrole as a byproduct, and the reaction was then optimized to give the trisubstituted pyrrole in 78% yield; the proposed reaction intermediates are shown in Scheme 35. 182…”

Section: Review Syn Thesis 5 the Blaise Reactionmentioning

confidence: 99%

Acetonitrile as a Building Block and Reactant

Hoff

2018

Synthesis

View full text Add to dashboard Cite

Acetonitrile is popular as a solvent for performing organic reactions, as a ligand in inorganic chemistry, as a mobile phase in chromatography, and as an electrolyte solvent in dye-sensitized solar cells. This is mainly due to its ability to dissolve both polar and nonpolar components. However, acetonitrile is also a valuable building block allowing atom-efficient transformations in synthetic organic chemistry. The aim of this review is to highlight synthetic transformations using acetonitrile, covering both classical approaches and modern strategies proceeding through radical intermediates or mediated by metal catalysis. Besides showcasing synthetic protocols useful for acetonitrile and analogues, warnings for when not to use acetonitrile as a solvent are also provided.1 Introduction2 Fundamental Reactions with Acetonitrile3 Cyanomethylation of Non-Aromatics4 The Acetonitrile Nitrogen as a Nucleophile5 The Blaise Reaction6 Synthesis of Pyridines7 Other Cyclization Reactions8 Cyanomethylation of Arenes and Heteroarenes9 Acetylation of Arenes Using Acetonitrile10 Synthesis of N-Arylacetamides11 Cyanation Using Acetonitrile as a Cyanide Source12 When To Avoid Acetonitrile as a Solvent13 Conclusion

show abstract

The Catalytic, Enantioselective Michael Reaction

et al. 2016

View full text Add to dashboard Cite

The catalytic enantioselective Michael reaction is the conjugate addition of a resonance‐stabilized carbanion to an electron‐poor olefin (an αβ‐unsaturated carbonyl compound or a related derivative) mediated by substoichiometric amounts of a chiral catalyst that enables stereocontrol in the newly generated stereocenter(s). This reaction allows the direct enantioselective construction of substituted 1,5‐dicarbonyl compounds or related architectures through the appropriate selection of the enolizable carbonyl compound employed as pronucleophile and the Michael acceptor. A variety of catalyst architectures have been described that make it possible to carry out this reaction with superior levels of chemical efficiency and high enantio‐ and stereocontrol, and also under conditions that tolerate a wide variety of functional groups. Both transition metal catalysis and organocatalysis have been employed as methodological approaches for carrying out this reaction in an enantioselective manner. This chapter describes different catalytic systems and methods developed for achieving enantioselective Michael reactions through the end of 2012, including a detailed mechanistic explanation of the different generic modes of substrate activation operating with each type of catalyst and their associated stereochemical aspects. The intention is to provide researchers interested in applying this methodology to their own synthetic strategies with a suitable starting point for identifying an efficient synthetic approach. In addition, the preparation of selected catalysts that are excellent for a particular pairing of substrates in this reaction, together with practical experimental protocols are described and some examples in which these methodologies have been applied to total synthesis have been included. This chapter is limited exclusively to those examples in which the final Michael addition product is obtained after protonation of the conjugate addition intermediate and therefore, tandem, domino, or cascade processes initiated by Michael reactions lie outside the scope of this work. Supplemental references are provided for articles published after the 2012 cut‐off date through the first half of 2015.

show abstract

Zinc and Trimethylsilyl Chloride Mediated Synthesis of 2,3,5-Trisubstituted Pyrrole Diesters from Nitriles and Ethyl Bromoacetate

Cited by 22 publications

References 11 publications

Recent Advancements in Pyrrole Synthesis

Recent Advancements in Pyrrole Synthesis

Acetonitrile as a Building Block and Reactant

The Catalytic, Enantioselective Michael Reaction

Contact Info

Product

Resources

About