133503-46-5Relevant articles and documents
Alkynylation/dearomatizative cyclization to construct spiro[5.5]undecanes
Shao, Jidong,Li, Liqi,Zhang, Jie,Hu, Jingping,Xue, Jijun,Li, Ying
, p. 31363 - 31366 (2016/04/09)
A new access to spiro[5.5]undecane frameworks was reported through the ZnMe2-promoted alkynylation of salicylaldehyde and HCO2H-mediated dearomatizative cyclization which can be used to construct an all-carbon quaternary spirocenter. This method can be applied to the rapid synthesis towards a series of useful motifs of natural products, such as the core of elatol and aphidicolin.
Directing group assisted nucleophilic substitution of propargylic alcohols via o -quinone methide intermediates: Br??nsted acid catalyzed, highly enantio- and diastereoselective synthesis of 7-alkynyl-12a-acetamido-substituted benzoxanthenes
Saha, Satyajit,Schneider, Christoph
supporting information, p. 648 - 651 (2015/03/05)
BINOL-based, chiral phosphoric acids catalyze the substitution of 1-(o-hydroxyphenyl)propargylic alcohols with enamides to furnish 7-alkynyl-12a-acetamido-substituted benzo[c]xanthenes and related heterocycles in a one-pot operation with excellent diastereo- and enantioselectivity. Ambient reaction temperature, operationally simple reaction conditions, low catalyst loading, high yields, and excellent stereocontrol are attractive features of this process and make it a highly practical and versatile transformation.
Synthesis of chromones through LiOtBu/air-mediated oxidation and regioselective cyclization of o-hydroxyphenyl propargyl carbinols
Zhang, Shuai,Wan, Changfeng,Wang, Qiang,Zhang, Baiqun,Gao, Lingfeng,Zha, Zhenggen,Wang, Zhiyong
, p. 2080 - 2083 (2013/05/09)
A cascade oxidative cyclization reaction for the synthesis of chromone derivatives was developed by using LiOtBu as a mediator and air as an oxidant. The reaction was carried out without the assistance of a transition metal under mild conditions to afford the chromones in good yields with high regioselectivities. A tandem reaction for the synthesis of various chromones was developed. LiOtBu was used as a mediator and air was used as a clean oxidant. The reaction generally showed high regioselectivity under mild conditions. Extensive research showed that dehydrogenative oxidation of the alcohols under strongly basic conditions was the crucial step, and Li+ was also found to play an important role in this process. Copyright
Synthesis of γ-benzopyranone by TfOH-promoted regioselective cyclization of o-alkynoylphenols
Yoshida, Masahito,Fujino, Yuta,Doi, Takayuki
supporting information; experimental part, p. 4526 - 4529 (2011/10/09)
Regioselective cyclization of o-alkynoylphenols forming γ-benzopyranones has been demonstrated. Trifluoromethanesulfonic acid (TfOH) induced 6-endo cyclization of o-alkynoylphenols without forming 5-exo cyclized benzofuranone derivatives to provide the corresponding γ-benzopyranones in high yields.
Regioselective synthesis of flavone derivatives via DMAP-catalyzed cyclization of o-alkynoylphenols
Yoshida, Masahito,Fujino, Yuta,Saito, Koya,Doi, Takayuki
experimental part, 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.
Identification of the major degradation products of 4-methoxy-2-(3- phenyl-2-propynyl)phenol formed by exposure to air and light
Schiavi,Serafini,Italia,Villa,Fronza,Selva
, p. 812 - 814 (2007/10/02)
Exposure of 4-methoxy-2-(3-phenyl-2-propynyl)phenol (CO/1828) to air and light (accelerated by temperature) yields 1-(2-hydroxy-5-methoxyphenyl)-3- phenylpropynone as the major degradation product. With extraction, this product rapidly degrades to 5-methoxyaurone and 6-methoxyflavone. In addition, a mixture of dimeric and heterodimeric compounds that are not fully identified was observed. These results indicate the formation of a reactive ortho-quinone methide as an unstable intermediate. This hypothesis is supported by evidence that the aurone slowly isomerizes into the flavone in control samples. Identification of compounds was accomplished with mass spectrometry, nuclear magnetic resonance spectrometry, UV-high-performance liquid chromatography, and comparison with authentic samples.
Substituted 2-alkynylphenols with anti-inflammatory action, a process for their preparation and pharmaceutical compositions thereof
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, (2008/06/13)
There are described new compounds of formula wherein, R and R1 are chosen independently from: hydrogen, hydroxyl, halogen, (C1 - C6) alkyl, (C1 - C4) alkoxy, benzyloxy, -COOR4;, R2 is : hydrogen, hydr
