Nickel nanoparticles catalyzed chemoselective Knoevenagel condensation of Meldrum’s acid and tandem enol lactonizations via cascade cyclization sequence
作者:Jitender M. Khurana、Kanika Vij
DOI:10.1016/j.tetlet.2011.05.032
日期:2011.7
A novel protocol has been reported wherein, polyethylene glycol (PEG) stabilized nickel nanoparticles have been used as catalyst for chemoselective Knoevenagel condensation of aromatic aldehydes and Meldrum’s acid to give 5-arylidene Meldrum’s acid which underwent tandem enol lactonization by Michael addition/cyclization sequence with active methylene compounds in the presence of Ni nanoparticles to
A Practical and Convenient Protocol for the Synthesis of (<i>E</i>)-α,β-Unsaturated Acids
作者:Amar R. Mohite、Ramakrishna G. Bhat
DOI:10.1021/ol402130t
日期:2013.9.6
α,β-Unsaturated acids are very useful and versatile reagents in organic synthesis. A novel, practical, and convenient catalytic protocol comprising FeCl3·6H2O (0.5 mol %) and H2O (1 equiv) in CH3NO2 is described for the rapid synthesis of α,β-unsaturated acids with high E-stereoselectivity under both microwave and conventional heating conditions with high TON and TOF values. This powerful approach
Tandem Molybdenum Catalyzed Hydrosilylations: An Expedient Synthesis of β-Aryl Aldehydes
作者:Christopher G. Frost、Benjamin C. Hartley
DOI:10.1021/ol701812w
日期:2007.10.1
The synthesis of beta-aryl aldehydes utilizing a tandem molybdenum catalyzed hydrosilylation is described. This new functional group interconversion provides an efficientmethod for the two-carbon homologation of aryl aldehydes.
An expedient stereoselective synthesis of ( E )- α,β -unsaturated esters and thioesters using FeCl 3 ·6H 2 O
作者:Amar R. Mohite、Trimbak B. Mete、Ramakrishna G. Bhat
DOI:10.1016/j.tetlet.2017.01.024
日期:2017.2
Facile and convenient synthesis of α,β-unsaturatedesters and thioesters from alkylidene derivatives of Meldrum’s Acid is described. This method uses catalytic amount of FeCl3·6H2O (0.001–0.005 equiv) with alcohols/thiols (1 equiv) in dry CH3NO2 followed by catalytic amount of piperidine. A variety of α,β-unsaturatedesters and thioesters have been synthesized with high E-stereoselectivity in good
描述了从Meldrum's Acid的亚烷基衍生物容易且方便地合成α,β-不饱和酯和硫代酯。该方法在干燥的CH 3 NO 2中使用催化量的FeCl 3 ·6H 2 O(0.001-0.005当量)与醇/硫醇(1当量),然后催化量的哌啶。已经以高至优异的产率合成了具有高E-立体选择性的多种α,β-不饱和酯和硫代酯。该方法的应用通过辛辛酸,防晒剂和其他对甲氧基肉桂酸酯的克规模合成得到证明。
Synthesis of Substituted 1,2,3,4-Tetrahydro-1-thiacarbazole and Spiro[pyrrolidinone-3,3′-indolinones] through a Common Intermediate Obtained by Condensation of Indolin-2-one, (Aryl)aldehydes, and Meldrum's Acid
Trimolecular adducts resulting from condensation between indolin-2-one (or indoline-2-thione), (aryl)aldehydes, and Meldrum’s acid are useful intermediates for the synthesis of either 1,2,3,4-tetrahydro-1-thiacarbazoles or spiro[pyrrolidino-3,3′-oxindoles] related to the natural product horsfiline. These latter compounds were obtained in a three-step procedure characterized by acyl azide formation