35487-34-4Relevant academic research and scientific papers
Transition-metal-free and facile synthesis of 3-alkynylpyrrole-2,4-dicarboxylates from methylene isocyanides and propiolaldehyde
Chen, Xiaojuan,Fu, Liping,Huo, Xiaoli,Shao, Jiaan,Yu, Liya,Zeng, Linghui,Zhang, Chong,Zhang, Jiankang,Zhu, Huajian
, p. 16430 - 16433 (2021/10/01)
A transition-metal-free, facile and efficient method for the synthesis of 3-alkynylpyrrole-2,4-dicarboxylates from methylene isocyanides and propiolaldehyde with moderate to good yields has been developed. The direct transformation process and good tolerance of various substituents make it an alternative approach to previous protocols, and potential applications of these investigated compounds are expected with or without post-modifications.
Gold-Catalyzed Synthesis of 2,5-Disubstituted Oxazoles from Carboxamides and Propynals
Xu, Yun,Wang, Qian,Wu, Yufeng,Zeng, Zhongyi,Rudolph, Matthias,Hashmi, A. Stephen K.
supporting information, p. 2309 - 2314 (2019/04/13)
2,5-Disubstituted oxazoles are synthesized by oxidative gold catalysis. In contrast to a reported procedure that delivers 2,4-disubstituted oxazoles starting from terminal alkynes, a switch in selectivity towards a 2,5-disubstitution is achieved by the use of propynals as starting materials. In the new reaction, the key intermediate is formed by the nucleophilic attack of the carboxamide onto a gold carbenoid, and then condensates with the more electrophilic aldehyde moiety already present in the substrate and not with the ketone that is derived from the oxygen donor. This new cyclization mode introduces a new carbonyl moiety as substituent at the 2,5-disubstituted oxazole, an attractive motive that can be found in bioactive compounds or be used for further derivatizations. (Figure presented.).
Catalyst-Free Annulation of 2-Pyridylacetates and Ynals with Molecular Oxygen: An Access to 3-Acylated Indolizines
Chen, Zhengwang,Liang, Pei,Ma, Xiaoyue,Luo, Haiqing,Xu, Guohai,Liu, Tanggao,Wen, Xiaowei,Zheng, Jing,Ye, Hui
, p. 1630 - 1639 (2019/01/26)
A catalyst and additive-free annulation of 2-pyridylacetates and ynals under molecular oxygen was the first developed, affording 3-acylated indolizines in good to excellent yields. Molecular oxygen was used as the source of the carbonyl oxygen atom in indolizines. This approach was compatible with a wide range of functional groups, and especially it has been successfully extended to unsaturated double bonds and triple bonds, which were difficult to prepare by previous methods in a single step.
Synthesis of (: Z)-β-halo α,β-unsaturated carbonyl systems via the combination of halotrimethylsilane and tetrafluoroboric acid
Da Silva, Vitor A. F.,Da Silva, Gustavo P.,Matsuo, Bianca T.,Ali, Akbar,Davis, Rebecca L.,Zukerman-Schpector, Julio,Corrêa, Arlene G.,Paix?o, Márcio W.
, p. 519 - 526 (2019/01/24)
A convenient and broadly applicable method for the hydrohalogenation of ynones is described, by the combination of halotrimethylsilanes and tetrafluoroboric acid. Practically, one equivalent of HX (Br?nsted acid) and BF3 (Lewis acid) is smoothly generated, which activates the carbonyl compounds. Through this protocol, 42 examples of (Z)-β-halovinyl carbonyl compounds (Cl, Br and I) were obtained, in good yields and high stereoselectivity having 2-MeTHF as a solvent.
Rhodium-Catalyzed 1,1-Hydroacylation of Thioacyl Carbenes with Alkynyl Aldehydes and Subsequent Cyclization
Zhou, Bingnan,Wu, Qiuyue,Dong, Ziyang,Xu, Jiaxi,Yang, Zhanhui
, p. 3594 - 3599 (2019/05/24)
A rhodium-catalyzed 1,1-hydroacylation of thioacyl carbenes with alkynyl and alkenyl aldehydes and subsequent 6-endo-trig/dig cyclization are realized, giving structurally diverse 4H-thiopyran-4-ones and 2,3-dihydro-4H-thiopyran-4-ones in moderate to good yields. The oxidative addition of Rh(I) to aldehydes is proposed to be the turnover-limiting step. Manipulations of estrones demonstrate the applications of our formal (3 + 3) transannulations in the structural modifications of natural products.
Development of new scaffolds as reversible tissue transglutaminase inhibitors, with improved potency or resistance to glutathione addition
Apperley, Kim Y. P.,Roy, Isabelle,Saucier, Vincent,Brunet-Filion, Nicholas,Piscopo, Sara-Pier,Pardin, Christophe,De Francesco, élise,Hao, Catherine,Keillor, Jeffrey W.
, p. 338 - 345 (2017/03/08)
Previous studies within our group have yielded a class of cinnamoyl-based competitive reversible inhibitors for tissue transglutaminase (TG2), with Ki values as low as 1.0 μM (compound CP4d). However, due to the electrophilic nature of their al
Zinc-catalyzed [4+3] cycloaddition with concomitant furan annulation: Formation of cyclohepta[b]furans
Song, Bo,Li, Lian-Hua,Song, Xian-Rong,Qiu, Yi-Feng,Zhong, Mei-Jin,Zhou, Ping-Xin,Liang, Yong-Min
, p. 5910 - 5913 (2014/05/20)
A convenient zinc-promoted [4+3] cycloaddition of a carbonyl ene-yne with simple dienes was first achieved. This reaction provided an efficient strategy to prepare various cyclohepta[b]furan rings by cascade cycloadditions. Additionally, a multicomponent reaction of dione, alkynal, and diene was also reported, which exhibited a novel strategy for selective creations of C-O bonds and C-C bonds. Go tandem! A first zinc-catalyzed tandem [4+3] cycloaddition is presented herein. Various substituted cyclohepta[b]furans were synthesized from carbonyl ene-yne and diene in moderate to good yield. Furan rings and seven-membered rings were prepared in one single step (see scheme; TBS=tert-butyldimethyl).
Catalytic Asymmetric Synthesis of Alkynyl Aziridines: Both Enantiomers of cis-Aziridines from One Enantiomer of the Catalyst
Guan, Yong,L?pez-Alberca, Maria P.,Lu, Zhenjie,Zhang, Yu,Desai, Aman A.,Patwardhan, Aniruddha P.,Dai, Yijing,Vetticatt, Mathew J.,Wulff, William D.
, p. 13894 - 13900 (2016/02/18)
Alkynyl aziridines can be obtained from the catalytic asymmetric aziridination (AZ reaction) of alkynyl imines with diazo compounds in high yields and high asymmetric inductions mediated by a chiral boroxinate or BOROX catalyst. In contrast to the AZ reaction with aryl- and alkyl-substituted imines, alkynyl imines react to give cis-substituted aziridines with both diazo esters and diazo acetamides. Remarkably, however, the two diazo compounds give different enantiomers of the cis-aziridine from the same enantiomer of the catalyst. Theoretical considerations of the possible transition states for the enantiogenic step reveal that the switch in enantiomers results from a switch from Si-face to Re-face addition to the imine, which in turn is related to a switch from reaction with an E-imine in the former and a Z-isomer of the imine in the latter. The imine did it: The aziridination of alkynyl imines with diazo esters and diazo acetamides gives cis-aziridines with very high enantioselectivities. The absolute configuration of the cis-aziridine is reversed for the two diazo compounds even though the same enantiomer of the catalyst is used. The alkynyl imines can isomerize under the reaction conditions and the enantiomeric switch is proposed to result from the preferential reaction of E-imine with diazo esters and Z-imines with diazo acetamides.
Efficient one-pot preparation of methylthio arylbutadiynes by double elimination protocol
Su, Qiong,Yan, Hong,Gao, Shi-Chao,Xie, De-Xun,Cai, Qing-Yun,Shao, Guang,Peng, Zhi-Hong,An, De-Lie
, p. 2648 - 2655 (2013/07/26)
A novel and efficient method for preparation of methylthio arylbutadiynes (Ar-C≡C-C≡C-SCH3) was described, and a series of compounds have been expediently obtained by the one-pot protocol starting from methylthiomethyl phenyl sulfone (MP-S) and arylpropargyl aldehydes. The mechanism was discussed on the basis of trapping and characterization of key intermediates. The results from experiments indicated that the reaction involved the initial nucleophilic addition of MP-S to arylpropargyl aldehydes to produce an intermediate carrying two leaving groups and subsequent double elimination reactions. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications to view the free supplemental file.
PROCESS FOR PRODUCING ALDEHYDES OR KETONES BY OXIDIZING ALCOHOLS WITH OXYGEN
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Page/Page column 4, (2012/09/10)
Provided is a process for producing aldehydes or ketones by oxidizing alcohols with oxygen, which comprises oxidizing alcohols to aldehydes or ketones in an organic solvent at room temperature with oxygen or air as an oxidant, wherein ferric nitrate (Fe(NO3)3.9H2O), 2,2,6,6-tetramethylpiperidine N-oxyl (TEMPO) and an inorganic chloride are used as catalysts, the reaction time is 1-24 hours, and the molar ratio of said alcohols, 2,2,6,6-tetramethylpiperidine N-oxyl and the inorganic chloride is 100:1?10:1?10:1?10. The present process has the advantages of high yield, mild reaction conditions, simple operation, convenient separation and purification, recoverable solvents, substrates used therefor being various and no pollution, and therefore it is adaptable to industrialization.
