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Tribromomethyl ketone and tribromovinyl derivatives were selectively prepared from the decarboxylative tribromination. The reaction between propiolic acid derivatives and dibromoisocyanuric acid (DBCA)/H2O afforded predominantly a tribromomethyl ketone derivative in the presence of AgOAc (10 mol%). When the same reaction was conducted with 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) instead of AgOAc, tribromovinyl derivatives were exclusively formed in good yields. It was found that ethynyl bromide is an intermediate. [ABSTRACT FROM AUTHOR]

2,2-Dichloro-1,2-diarylethanones were synthesized from diarylalkynes and trichloroisocyanuric acid. The reaction was conducted in CH3CN/H2O at room temperature for 12 h. In addition, the desired 2,2-dichloro-1,2-diarylethanones could be prepared from aryl bromides and propiolic acid through se-quential Pd-catalyzed decarboxylative coupling and chlorination. This method showed moderate to good yields and good tolerance toward functional groups such as chlorides, bromides, aldehydes, and ketones. [ABSTRACT FROM AUTHOR]

2,2,2-Trichloroacetophenone derivatives were synthesized via decarboxylative trichlorination from arylpropiolic acids and trichloroisocyanuric acid (TCCA). The reaction was performed in the presence of water at room temperature, and the desired products were obtained in good yields. The reaction showed good functional group tolerance towards halide, cyano, nitro, ketone, ester and aldehyde groups. In addition, the 2,2,2-trichloroacetophenone derivatives were readily transformed into esters, amides, and hydrazides. Based on experiments with H218O (water-18O), we proposed a cationic reaction pathway as the mechanism and suggested two different pathways for producing aryl- and alkyl-substituted propiolic acids. [ABSTRACT FROM AUTHOR]

The reaction of alkynyl carboxylic acids, glyoxylic acid derivatives, and amines in the presence of a copper catalyst afforded the corresponding propargyl amines in good yields. The alkynyl carboxylic acid of this coupling reaction shows similar reactivity to that of a terminal alkyne, and the reactivity of the glyoxylic acid is almost identical to that of an aldehyde. When 2-aminopyridine was employed as the amine source, imidazopyridine derivatives were formed in good yields. [ABSTRACT FROM AUTHOR]

A double decarboxylative coupling reaction was developed. Alkynyl carboxylic acids, glyoxylic acid, and amines were reacted in the presENce of a copper catalyst to afford the corresponding propargyl amines in good yields. It was found that the alkynyl carboxylic acid showed similar reactivity to a terminal alkyne, and the reactivity of glyoxylic acid was almost idENtical to that of an aldehyde in this coupling reaction. More information can be found in the full paper by S. Lee and co ‐ workers on page   770 in Issue 6, 2016 (DOI: 10.1002/ajoc.201600109). [ABSTRACT FROM AUTHOR]

Nickel-catalyzed decarboxylative coupling reactions between aryl alkynyl carboxylic acids and arylboronic acids were developed. When aryl alkynyl carboxylic acids were reacted with arylboronic acids in the presence of NiCl 2 (10 mol %), 2,2′-bipyridine (20 mol %), Na 2 CO 3 (1.0 equiv), and Ag 2 CO 3 (1.0 equiv) in DMF at 80 °C for 18 h, the corresponding diaryl alkynes products were formed in moderate to good yields. [ABSTRACT FROM AUTHOR]

Novel substrates are applied in the palladium-catalyzed decarboxylative allylic alkylation. [ABSTRACT FROM AUTHOR]

An abstract of the article "Synthesis of Terminal Allenes via a Copper-Catalyzed Decarboxylative Coupling Reaction of Alkynyl Carboxylic Acid" by J. Lim et al. is presented.