92965-01-0Relevant articles and documents
(Ar-tpy)RuII(ACN)3: A Water-Soluble Catalyst for Aldehyde Amidation, Olefin Oxo-Scissoring, and Alkyne Oxygenation
Joarder, Dripta De,Gayen, Subrata,Sarkar, Rajarshi,Bhattacharya, Rajarshi,Roy, Sima,Maiti, Dilip K.
, p. 8468 - 8480 (2019/07/03)
The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)RuII(ACN)3, utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for tuning the catalytic activity of the Ru(II) complex. These complexes displayed excellent catalytic activity for several oxidative organic transformations including late-stage C-H functionalization of aldehydes with NH2OR to valuable primary amides in nonconventional aqueous media with excellent yield. Its diverse catalytic power was established for direct oxo-scissoring of a wide range of alkenes to furnish aldehydes and/or ketones in high yield using a low catalyst loading in the water. Its smart catalytic activity under mild conditions was validated for dioxygenation of alkynes to highly demanding labile synthons, 1,2-diketones, and/or acids. This general and sustainable catalysis was successfully employed on sugar-based substrates to obtain the chiral amides, aldehydes, and labile 1,2-diketones. The catalyst is recovered and reused with a moderate turnover. The proposed mechanistic pathway is supported by isolation of the intermediates and their characterization. This multifaceted sustainable catalysis is a unique tool, especially for late-stage functionalization, to furnish the targeted compounds through frequently used amidation and oxygenation processes in the academia and industry.
Generation of 4-iodoisocoumarins through a TBAI-mediated oxidative cyclization of 2-alkynoates
Luo, Jin,He,Chen,Li
, p. 1786 - 1792 (2018/06/18)
A tetra-butylammonium iodide (TBAI)-mediated oxidative iodocyclization of 2-alkynoates for the synthesis of various 4-iodoisocoumarin is described herein, and the reaction is highly efficient and shows broad functional group tolerance. This newly develope
NBS-Mediated Oxygen Transfer Reaction of Carbonyl in Ester: Efficient Synthesis of Benzil–o-carboxylate Derivative From o-Alkynylbenzoate
Yuan, Si-Tian,Wang, Yan-Hua,Liu, Jin-Biao,Qiu, Guanyinsheng
supporting information, p. 1981 - 1989 (2017/06/09)
A neighbouring ester group-participated diketonization of o-alkynylbenzoate is described here for the synthesis of benzil-o-carboxylate. Application of the resulting benzil-o-carboxylate in the synthesis of quinoxalines is also reached from o-alkynylbenzoate in an one-pot fashion. This diketonization proceeds smoothly with a high regioselectivity under mild conditions. Importantly, neighbouring group plays an important role in diketonization. A plausible mechanism suggests that a bromo-incoporated isocoumarin cation is described as an intermediate, and the whole process is constituted by NBS-mediated electrophilic 6-endo annulation and oxygen transfer reaction through NBS-mediated oxidative ring-opening. Water serves as a nucleophile of ring-opening. (Figure presented.).
