36315-64-7Relevant academic research and scientific papers
Quantification of the electrophilic reactivities of aldehydes, imines, and enones
Appel, Roland,Mayr, Herbert
supporting information; experimental part, p. 8240 - 8251 (2011/07/29)
The rates of the epoxidation reactions of aldehydes, of the aziridination reactions of aldimines, and of the cyclopropanation reactions of α,β-unsaturated ketones with aryl-stabilized dimethylsulfonium ylides have been determined photometrically in dimethyl sulfoxide (DMSO). All of these sulfur ylide-mediated cyclization reactions as well as the addition reactions of stabilized carbanions to N-tosyl-activated aldimines have been shown to follow a second-order rate law, where the rate constants reflect the (initial) CC bond formation between nucleophile and electrophile. The derived second-order rate constants (log k2) have been combined with the known nucleophilicity parameters (N, sN) of the aryl-stabilized sulfur ylides 4a,b and of the acceptor-substituted carbanions 4c-h to calculate the electrophilicity parameters E of aromatic and aliphatic aldehydes (1a-i), N-acceptor-substituted aromatic aldimines (2a-e), and α,β-unsaturated ketones (3a-f) according to the linear free-energy relationship log k 2 = sN(N + E) as defined in J. Am. Chem. Soc.2001, 123, 9500-9512. The data reported in this work provide the first quantitative comparison of the electrophilic reactivities of aldehydes, imines, and simple Michael acceptors in DMSO with carbocations and cationic metal-π complexes within our comprehensive electrophilicity scale.
Sequential double olefination of 2-(arylmethylidene)-2- phosphonoacetonitrile with dimsyl lithium and aldehydes: A domino route to densely substituted 1,3-butadienes
Chowdhury, Raghunath,Ghosh, Sunil K.
experimental part, p. 3868 - 3874 (2009/04/08)
An efficient and highly stereoselective synthesis of densely substituted 1,3-dienes has been achieved which entails a sequential double olefination of 2-(arylmethylidene)-2-phosphonoacetonitriles by a one-pot domino process involving Michael addition of d
A highly stereoselective knoevenagel reaction of N-tosylimines with active methylene compounds in DMSO
Chiba, Ryoichi,Oriyama, Takeshi
experimental part, p. 1218 - 1219 (2009/12/01)
In the presence of molecular sieves (MS) 4A in dimethyl sulfoxide (DMSO), a highly stereoselective Knoevenagel reaction of various N-tosylimines with active methylene compounds proceeded smoothly, producing the corresponding Knoevenagel products in high to excellent yields. Copyright
A convenient synthesis of (E)-α-cyano and (E)-α-ethoxycarbonyl vinylphosphonates
Shen, Yanchang,Jiang, Guo-Fang
, p. 140 - 141 (2007/10/03)
A new olefination catalysed by a base (KOBu(t)) and its application to the stereoselective synthesis of substituted (E)-α-cyano and (E)-α- ethoxycarbonyl vinylphosphonates is described.
