98153-26-5Relevant articles and documents
One Pot Synthesis of γ-Benzopyranones via Iron-Catalyzed Aerobic Oxidation and Subsequent 4-Dimethylaminopyridine Catalyzed 6-endo Cyclization
Zhai, Di,Chen, Lingzhu,Jia, Minqiang,Ma, Shengming
, p. 153 - 160 (2017/11/23)
One-pot synthesis of γ-benzopyranones was realized in decent yields and excellent regioselectivities via iron-catalyzed aerobic oxidation and 4-dimethylaminopyridine-catalyzed cyclization of related propargylic alcohols. Derivatizations to aromatic substituted γ-benzopyranones and synthesis of naturally occurring 3′,4′-dimethoxyflavone have also been realized. (Figure presented.).
Regioselective synthesis of flavone derivatives via DMAP-catalyzed cyclization of o-alkynoylphenols
Yoshida, Masahito,Fujino, Yuta,Saito, Koya,Doi, Takayuki
, p. 9993 - 9997 (2012/02/06)
A catalytic amount of DMAP promoted cyclization of o-alkynoylphenols via a 6-endo cyclization mode leading to flavone derivatives in high yields without forming 5-exo cyclized aurone derivatives. Utilizing this method, methoxy substituted flavone and alkyl substituted γ-benzopyranone derivatives were synthesized.
Synthesis of Highly Functionalized Flavones and Chromones Using Cycloacylation Reactions and C-3 Functionalization. A Total Synthesis of Hormothamnione
McGarry, Lynda W.,Detty, Michael R.
, p. 4349 - 4356 (2007/10/02)
The cycloacylations of hydroxy- and methoxy-substituted phenols with aryl- and alkylpropiolic acids using Eaton's reagent (10percent phosphorus pentoxide in methanesulfonic acid) gives highly substituted flavones and chromones in up to 63 percent yield.Styrylchromones were prepared from 2-methylchromones by condensation reactions of the 2-methyl group with various substituted benzaldehydes in sodium ethoxide and ethanol in almost quantitative yield.Methylation or hydroxylation at C-3 of these highly substituted flavones and styrylchromones was accomplished in a highly regioselective manner employing lithium diisopropylamide followed by quenching with an electrophile.Quenching of the initial anion with methyl triflate gave 3-methyl products while quenching of the initial anion with trimethylborate followed by oxidation gave 3-hydroxy products.A total synthesis of the naturally occurring styrylchromone hormothamnione, containing a 3-methyl substituent, is reported by use of these synthetic techniques.
