16619-67-3Relevant articles and documents
Pd catalyzed couplings of “superactive esters” and terminal alkynes: Application to flavones and γ-benzopyranones construction
Yang, Dandan,Wang, Zhenhua,Wang, Xiu,Sun, Huaming,Xie, Zunyuan,Fan, Juan,Zhang, Guofang,Zhang, Weiqiang,Gao, Ziwei
, p. 24 - 29 (2016/12/09)
Lewis base, N-methylmorpholine (NMM) accelerated Pd-catalyzed Sonogashira coupling of steric hindered super active esters, 1a–1e, and terminal alkynes. This approach provided an efficient synthetic protocol for a broad array of acylated o-alkynoylphenols compounds, 3a–3e, under moderate conditions. The mechanistic study clearly demonstrated that NNM stabilized the catalytic palladium species, and accelerated the leaving of triazine moiety during the catalytic cycle of the cross-coupling reactions. In addition, piperazine was found to efficiently catalyze the 6-endo cyclization of acylated o-alkynoylphenols, which achieved the diversity oriented synthesis of γ-benzopyranones, 4aa–4eg, with 93–99% yields.
Highly Selective and Modular Synthesis of 3-Aryl-4-(arylethynyl)-2H-chromen-2-ones from 2-Iodoaryl 2-Arylacetates through a Carbonylative Sonogashira Coupling–Intramolecular Aldol Cascade Reaction
Chandrasekhar, Attoor,Ramkumar, Venkatachalam,Sankararaman, Sethuraman
, p. 4041 - 4049 (2016/08/24)
A modular method for the synthesis of 3-aryl-4-(arylethynyl)-2H-chromen-2-ones from 2-iodoaryl 2-arylacetates and arylacetylenes has been developed. The carbonylative Sonogashira coupling–intramolecular aldol casade reaction was carried out in the presence of Pd(PPh3)2(Cl)2as the catalyst. The one-pot approach that involves the in situ formation of the 2-iodoaryl 2-arylacetates from the corresponding 2-iodophenols and 2-arylacetyl chlorides followed by the palladium-catalyzed carbonylative annulation in the presence of the arylacetylene has also been described for the formation of the 3-aryl-4-(arylethynyl)-2H-chromen-2-ones.
A concise synthesis of 3-aroylflavones via Lewis base 9-azajulolidine- catalyzed tandem acyl transfer-cyclization
Yoshida, Masahito,Saito, Koya,Fujino, Yuta,Doi, Takayuki
supporting information, p. 11796 - 11798,3 (2020/10/15)
Lewis base-catalyzed tandem acyl transfer-cyclization of acylated o-alkynoylphenols leading to 3-aroylflavones was developed. 9-Azajulolidine smoothly promoted the reaction of the aroyl derivatives at ambient temperature, and the structure-diversed synthesis of 3-aroylflavones with distinct substituents was achieved in moderate to excellent yields.
