20413-06-3Relevant academic research and scientific papers
Magnesium Halide-Catalyzed Synthesis of Oxaspiro[2.5]octenes from a Methylenecyclopropane and Acyl Cyanoalkenes
Ogura, Kazuki,Shibata, Ikuya,Shimazu, Jun-ya,Suzuki, Itaru
supporting information, p. 2785 - 2787 (2021/06/26)
MgX2-catalyzed annulation of methylenecyclopropanes with acyl cyanoalkenes was accomplished to give oxaspiro[2.5]octenes in excellent yields. The reaction proceeded through a rare intramolecular oxa-Michael addition of Mg enolate. The oxaspiro
Substituent-Controlled Divergent Cascade Cycloaddition Reactions of Chalcones and Arylalkynols: Access to Spiroketals and Oxa-Bridged Fused Heterocycles
Chang, Weixing,Kong, Jingyang,Li, Jing,Liu, Lingyan,Wang, Hongkai,Zeng, Tianlong
supporting information, p. 4024 - 4032 (2021/07/12)
Herein, we report substituent-controlled divergent cascade cycloaddition reactions of chalcones and arylalkynols in the presence of PtI2. Depending on the substituent on the chalcone, either spiroketals or oxa-bridged fused heterocycles could be obtained in the ranges of 86–97% and 87–95% yields under identical reaction conditions. Control experiments were carried out to elucidate the origin of the high chemoselectivity. These provide a method for the synthesis of a diverse array of structurally complex oxygen-containing heterocycles. (Figure presented.).
Dienamine-Mediated Asymmetric Inverse-Electron-Demand Hetero-Diels–Alder Reaction of Linear Deconjugated Enones: Diversity-Oriented Synthesis of 3,4-Dihydropyrans
Maity, Rajendra,Pan, Subhas Chandra
supporting information, p. 871 - 874 (2017/02/15)
The first organocatalytic asymmetric inverse-electron-demand Diels–Alder reaction of deconjugated enones by using a linear dienamine was explored. Electron-poor oxadienes having a cyano group were found to be suitable in this reaction. With a 20 mol-% loa
Organocatalytic Asymmetric [4+2] Cycloaddition of 1-Acetylcyclopentene and 1-Acetylcyclohexene for the Synthesis of Fused Carbocycles
Nath, Utpal,Pan, Subhas Chandra
supporting information, p. 6457 - 6461 (2017/12/01)
The first organocatalytic asymmetric [4+2]-cycloaddition reaction of 1-acetylcyclopentenes and 1-acetylcyclohexenes was developed. Enones having cyano groups were used as the dienophiles in this method. The reaction provides a useful practical route to th
Reduced graphene oxide supported piperazine in aminocatalysis
Rodrigo, Eduardo,García Alcubilla, Beatriz,Sainz, Raquel,Fierro, J. L. García,Ferritto, Rafael,Cid, M. Belén
supporting information, p. 6270 - 6273 (2014/06/09)
Reduced graphene oxide (rGO) has been used as a support for piperazine to provide a heterogeneous bifunctional organocatalyst (rGO-NH) that is able to efficiently promote vintage organic transformations such as Knoevenagel, Michael and aldol reactions. The obtained results suggest a significant role of the support in the course of these reactions. This journal is the Partner Organisations 2014.
Microwave synthesis of α-cyano chalcones
Deshpande, Shyam J.,Leger, Paul R.,Sieck, Stephen R.
supporting information; experimental part, p. 1772 - 1775 (2012/05/04)
A novel methodology for facile production of α-cyano chalcones under microwave irradiation is described. Utilizing a Knoevenagel condensation between benzoylacetonitriles and aromatic aldehydes, substituted chalcones are generated via a 15-min, one-pot synthesis. Diversification of aromatic groups, including electron-withdrawing, electron-donating, and heterocyclic substitutions, has led to the isolation of over twenty colored, solid chalcone products. Furthermore the methodology can be extended to the synthesis of benzylidenemalononitriles as well as methyl and ethyl α-cyano cinnamates.
Tandem cross-Rauhut-Currier/cyclization reactions of activated alkenes to give densely functionalized 3,4-dihydropyrans
Liu, Wen,Zhou, Jing,Zheng, Changwu,Chen, Xingkuan,Xiao, Hua,Yang, Yingquan,Guo, Yinlong,Zhao, Gang
supporting information; experimental part, p. 1768 - 1773 (2011/04/15)
A novel tandem cross-Rauhut-Currier/cyclization reaction between α,β-unsaturated ketones was developed. Using DABCO (20 mol %) as the catalyst, a series of densely functionalized 3,4-dihydropyrans were obtained in excellent yields and stereoselectivities (up to 98% yield, >99:1 dr). A tentative catalytic cycle was proposed with key intermediates confirmed by ESIMS studies.
New routes to the synthesis of pyridazinone, ethoxypyridine, pyrazole and pyrazolo[1,5-a]pyrimidine derivatives incorporating a benzotriazole moiety
Al-Omran,El-Hay,El-Khair
, p. 1617 - 1622 (2007/10/03)
A new approach to the synthesis of pyridazinone, ethoxypyridine, pyrazole and 7-aminopyrazolo-[1,5-a]pyrimidine derivatives. The structure of the newly synthesized compounds was elucidated by elemental analyses, ir, 1H nmr spectra and in some cases by 13C nmr investigations.
Hetero-Diels-Alder Reaction of 3-Aryl-2-benzoyl-2-propenenitriles with Enol Ethers. Synthesis of 2-Alkoxy-3,4-dihydro-2H-pyran-5-carbonitriles
Bogdanowicz-Szwed,Palasz
, p. 1157 - 1172 (2007/10/03)
The hetero-Diels-Alder reaction of 3-aryl-2-benzoyl-2-propenenitriles 1a-d with enol ethers 2a-c yields cis/trans diastereoisomers of 2-alkoxy-4,6-diaryl-3,4-dihydro-2H-pyran-5-carbonitriles 3 and 4 in 79-98% yield. The similar reaction of 1a-c with cyclic enol ether 5 affords diastereoisomeric cycloadducts 6 and 7 with cis annulated pyran rings. Reaction of 3 with sulfuric acid leads to 2-hydroxy-3,4-dihydro-2H-pyran-5-carbonitriles 8 and 9.
Silica-Gel-Catalysed Knoevenagel Condensation of Peptidyl Cyanomethyl Ketones with Aromatic Aldehydes and Ketones. A Novel Michael Acceptor Functionality for C-Modified Peptides: The Benzylidene and Alkylidene Cyanomethyl Ketone Function
Brillon, Denis,Sauve, Gilles
, p. 1838 - 1842 (2007/10/02)
Simple preparation of cyanomethyl ketone derivatives 5a-5b of N-acetylphenylalanine and N-acetylleucylphenylalanine is accomplished by condensation of the corresponding activated carboxylic acids 3a-3b and the carbanion of tert-butyl cyanoacetate to give
