Base and catalyst-free synthesis of nitrobenzodiazepines via a cascade N-nitroallylation-intramolecular aza-Michael addition involving o-phenylenediamines and nitroallylic acetates

A high-yielding cyclocondensation of 4-hydroxycoumarin, phenylglyoxal monohydrate, and heteroarylamines proceeds without catalysis, which gives novel functionalized furo[3,2-c]coumarins and heteroarylamino alkylation of coumarin products in acetonitrile under reflux, is reported for the first time. This tandem process involves sequentially an aldol condensation, Michael addition, a ring closure, and dehydration reaction.

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Diversity-Oriented Synthesis via Catalyst-Free Addition of Ketones to [e]-Fused 1H-Pyrrole-2,3-diones

Synthesis ◽

10.1055/s-0037-1610647 ◽

2018 ◽

Vol 50 (24) ◽

pp. 4897-4904 ◽

Cited By ~ 3

Author(s):

Ekaterina Stepanova ◽

Andrey Maslivets ◽

Svetlana Kasatkina ◽

Maksim Dmitriev

Keyword(s):

Intramolecular Cyclization ◽

Aromatic Hydrocarbons ◽

Michael Addition ◽

Aldol Reaction ◽

Synthetic Approach ◽

Reaction Conditions ◽

Diversity Oriented Synthesis ◽

Catalyst Free ◽

Solvent Free Conditions ◽

Reaction Proceeds

A facile synthetic approach towards two distinct pyrrole-based heterocyclic scaffolds has been developed by the interaction of 1H-pyrrole-2,3-diones fused at the [e]-side to a 1,4-benzoxazin-2-one or quinoxalin-2(1H)-one moiety with ketones. The described interaction proceeds either as an aldol reaction or as a Michael addition/intramolecular cyclization depending on the reaction conditions. The disclosed aldol reaction proceeds with good diastereoselectivity under catalyst-free conditions when the reaction is carried out in aromatic hydrocarbons. Products of the cascade Michael addition/intramolecular cyclization reaction are predominantly formed under catalyst-free and solvent-free conditions. The proposed strategy provides facile access to pharmaceutically interesting pyrrole-based polyheterocycles.

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Substrate-controlled Diastereoselective Michael Addition of Alkylidene Malonates by Grignard Reagents

Heterocyclic Communications ◽

10.1515/hc-2019-0019 ◽

2019 ◽

Vol 25 (1) ◽

pp. 116-121

Author(s):

Wei Zhou ◽

Qingwei Xiao ◽

Yuanyuan Chang ◽

Qifa Liu ◽

Xiaohao Zang ◽

...

Keyword(s):

Amino Acid ◽

Asymmetric Synthesis ◽

Michael Addition ◽

Chiral Auxiliary ◽

Grignard Reagents ◽

Amino Acid Derivatives ◽

Catalyst Free ◽

Chemical Efficiency

AbstractHerein is described a diastereoselective Michael addition of Grignard reagents to α, β- unsaturated diethyl malonates incorporated with a 2-oxazolidone chiral auxiliary. The catalyst-free Michael addition proceeds with good chemical efficiency and excellent stereoselectivity; and it provides new thoughts to the asymmetric synthesis of β-substituted β3 amino acid derivatives.

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Tetramethylguanidium Lactate Ionic Liquid: Catalyst-free Medium for Michael Addition Reaction

Chemical Research in Chinese Universities ◽

10.1016/s1005-9040(08)60009-4 ◽

2008 ◽

Vol 24 (1) ◽

pp. 36-41 ◽

Cited By ~ 4

Author(s):

D LIANG

Keyword(s):

Ionic Liquid ◽

Michael Addition ◽

Addition Reaction ◽

Free Medium ◽

Michael Addition Reaction ◽

Catalyst Free

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ChemInform Abstract: Microwave-Promoted Catalyst-Free Benzylic C-H Functionalization of Methyl Quinoline and Michael Addition to β-Nitrostyrene.

ChemInform ◽

10.1002/chin.201324137 ◽

2013 ◽

Vol 44 (24) ◽

pp. no-no

Author(s):

N. Nageswara Rao ◽

H. M. Meshram

Keyword(s):

Michael Addition ◽

Catalyst Free

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Synthesis of functionalized isoxazole–oxindole hybrids via on water, catalyst free vinylogous Henry and 1,6-Michael addition reactions

RSC Advances ◽

10.1039/c5ra14039k ◽

2015 ◽

Vol 5 (100) ◽

pp. 81768-81773 ◽

Cited By ~ 15

Author(s):

Sakkani Nagaraju ◽

Neeli Satyanarayana ◽

Banoth Paplal ◽

Anuji K. Vasu ◽

Sriram Kanvah ◽

...

Keyword(s):

Michael Addition ◽

Addition Reaction ◽

Addition Reactions ◽

Michael Addition Reaction ◽

Henry Reaction ◽

Catalyst Free

Various isoxazole–oxindole hybrids were synthesized via vinylogous Henry reaction of 3,5-dimethyl-4-nitroisoxazole and isatin under catalyst free conditions in water. The products obtained were functionalized using 1,6-Michael addition reaction.

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