Copper-Catalyzed One-Pot Synthesis of Functionalized 1,4-Dihydroazete Derivatives from Sulfonyl Azides, Terminal Alkynes, and Tetramethylguanidine

Abstract

Ketenimine intermediates generated by the addition of copper acetylides to sulfonyl azides are trapped by tetramethylguanidine to afford 1,4-dihydro-N,N-dimethyl-3-aryl(alkyl)-4-aryl(alkyl)sulfoniminoazet-2-amine derivatives in moderate to good yields.

A Novel Synthesis of Tetrasubstituted Pyrroles via Tandem Benzylic Oxidative Cyclization

“…18 In recent years, several reports of benzylic C-H functionalization have been published. [18][19][20][21][22][23][24][25][26][27][28] As part of our current studies on the development of new multicomponenent reactions to synthesize novel functional heterocycles, [29][30][31][32] we herein report a domino reaction between primary benzylamines and dialkyl acetylenedicarboxylates, in the presence of potassium cyanide for the synthesis of tetrasubstituted pyrroles. This work is an extension of our recent report that the reaction between benzylamine (1 mmol) and dialkyl acetylenedicarboxylates (2 mmol) in the presence of N-methylimidazole (0.05 mmol) as an organocatalyst gives trialkyl 1-benzyl-6-oxo-1,6-dihydro-2,3,4-pyridinetricarboxylates in good yields.…”

1- and 2-Azetines via Visible Light-Mediated [2 + 2]-Cycloadditions of Alkynes and Oximes

“…Currently available approaches to access 1-azetines include β-eliminations − ( 4 ), thermolysis of cyclopropyl azides − ( 5 ), and ring expansion reactions of aziridines ( 6 ) (Figure B). Synthesis of 2-azetines is similarly limited, relying on eliminations − ( 7 ) and metal mediated cycloadditions via ring expansion of diazoaziridines ( 8 ). Arguably, [2 + 2]-cycloadditions between alkenes and nitriles , or alkynes and imines − represent the most efficient strategies to access 1- and 2-azetines; however, they suffer from a limited scope and the competing formation of azadiene byproducts ( 12 and 16 , Figure C) .…”

Copper‐Catalyzed N‐Arylation of Polysubstituted Pyridines Synthesized by the Novel Reaction of N‐Sulfonyl Ketenimine and Malononitrile‐Trichloroacetonitrile Adduct

“…The major advantages that we see in N ‐sulfonyl ketenimine participated reactions are mild reaction conditions, high level of selectivity, lesser side reactions, and high reaction yields. We may react this reagent with many various substrates to acquire so different scaffolds .…”