3159-07-7Relevant articles and documents
The behaviour of some thioxanthene and thianthrene derivatives with hydrazoic acid
Palazzo,Giannola,Caronna
, p. 839 - 841 (1974)
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Diversity in Heterocycle Synthesis Using α-Iminocarboxylic Acids: Decarboxylation Dichotomy
Laha, Joydev K.,Hunjan, Mandeep Kaur
, p. 2315 - 2323 (2022/02/07)
Despite the structural similarity with imines, α-iminocarboxylic acids have seldom been used in heterocycles synthesis. The reactions of ortho-substituted anilines and arylglyoxylic acids in DMSO at 40 °C gave various benzo-fused five- to six-membered N-heterocycles in good to excellent yields. The reaction proceeds via intramolecular Michael addition of α-iminocarboxylic acids, generated in situ, with an ortho-substituted nucleophile, yielding an isolable unprecedented tetrahedral carboxylic acids, which upon decarboxylation without any aid of additional reagents forms the N-heterocycles. DMSO is crucial in this reaction, perhaps because of improved solubility and the ease of decarboxylation of these tetrahedral carboxylic acids. However, a copper-catalyzed reaction of ortho-substituted anilines and 2-bromoarylglyoxylic acids gave a dibenzo-fused seven-membered N-heterocycle under a basic reaction condition. Unlike intramolecular cyclization with α-iminocarboxylic acids in the first case, α-iminocarboxylic acid undergoes a competitive decarboxylation under the copper-catalyzed conditions, which upon subsequent heteroarylation form the heterocycles. Taken together, the study described herein represents two different modes of decarboxylation observed with α-iminocarboxylic acids, leading to the synthesis of divergent heterocycles and pharmaceuticals, which remained unexplored previously.
Reductive Condensation of a Nitro Group with Carboxylic Acids Promoted by Phosphorus(III) Compounds: A Short Route to 5 H -Dibenzo[ b, e ][1,4]diazepin-11(10 H)-ones
Tryniszewski, Micha?,Bujok, Robert,Gańczarczyk, Roman,Wróbel, Zbigniew
, p. 3086 - 3094 (2020/08/10)
Tributyl- or triphenylphosphine promotes a one-pot, three-step method for the synthesis of differently substituted dibenzodiazepinones from N -aryl-2-nitroanilines. Pyridine analogues and the corresponding thiazepinones can also be formed using this method. The process involves deoxygenation of the nitro group, then formation of an iminophosphorane intermediate and its intramolecular condensation with a carboxyl group placed in the N -aryl group. The role of the carboxyl group in the formation of the iminophosphorane and the mode of cyclization are discussed.
COtab: Expedient and Safe Setup for Pd-Catalyzed Carbonylation Chemistry
Collin, Hugo P.,Reis, Wallace J.,Nielsen, Dennis U.,Lindhardt, Anders T.,Valle, Marcelo S.,Freitas, Rossimiriam P.,Skrydstrup, Troels
supporting information, p. 5775 - 5778 (2019/08/26)
Bench-stable tablets (COtabs) have been developed for the rapid and safe production of carbon monoxide. The tablets can be made in less than 5 min without the use of a glovebox and only require a stock solution of an amine base to liberate a specific quantity of CO in a two-chamber system. The COtabs were tested in five different carbonylation reactions and provided similar yields compared to literature procedures. Finally, a gram-scale reaction was conducted, as well as 13C-isotope labeling of the anticancer drug, olaparib.
