1403475-65-9Relevant academic research and scientific papers
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.
Synthesis of flavones and γ-benzopyranones using mild sonogashira coupling and 18-crown-6 ether mediated 6-endo cyclization
Chuang, Da-Wei,El-Shazly, Mohamed,Balaji D., Barve,Chung, Yu-Ming,Chang, Fang-Rong,Wu, Yang-Chang
, p. 4533 - 4540,8 (2020/08/31)
An efficient method for the synthesis of flavones and γ- benzopyranones has been developed utilizing a mild Sonogashira coupling and 18-crown-6 ether mediated 6-endo cyclization of o-alkynoylphenyl acetates. By using this strategy, flavones and γ-benzopyranones bearing electron-donating groups, halogens, and simple alkyl substituents were synthesized in satisfactory yields. A facile, mild, and selective method for the synthesis of flavones and γ-benzopyranones is reported. o-Alkynoylphenyl acetates were obtained from either acyl chloride derivatives or substituted salicylates. Upon removing the acetate group, flavones and γ- benzopyranones were synthesized within 15 min with the aid of 18-crown-6 ether. A library of flavones and γ-benzopyranones was established. Copyright
