13466-29-0Relevant articles and documents
Insertion and fragmentation of 2-ferrocenylmethylidene-1, 3-diketones upon their reactions with N-methylhydrazine
Klimova, Elena I.,Vazquez Lopez, Eduardo A.,Martinez Mendoza, Juan M.,Ramirez, Lena Ruiz,Alamo, Marcos Flores,Backinowsky, Leon V.
, p. 484 - 491 (2009)
(Chemical Equation Presented) Reactions of 2-ferrocenylmethylidene-1,3- diketones (1a-c) with methylhydrazine afford mainly insertion products (~40-58%), viz., 1-(N′-acyl-N′-methylhydrazino)-1-ferrocenyl-2- acylethanes (7a-d), together with lesser amounts
One-Pot Catalytic Enantioselective Synthesis of 2-Pyrazolines
Thomson, Connor J.,Barber, David M.,Dixon, Darren J.
supporting information, p. 2469 - 2473 (2019/02/01)
A scalable, one-pot, enantioselective catalytic synthesis of 2-pyrazolines from beta-substituted enones and hydrazines is described. Pivoting on a two-stage catalytic Michael addition/condensation strategy, the use of an aldehyde to generate a suitable hydrazone derivative of the hydrazine was found to be key for curtailing background reactivity and tuning the catalyst-controlled enantioselectivity. The new synthetic method is easy to perform, uses a new and readily prepared cinchona-derived bifunctional catalyst, is broad in scope, and tolerates a range of functionalities with high enantioselectivity (up to >99:1 e.r.). The significant scalability of this methodology was demonstrated with the synthesis of more than 80 grams of a pyrazoline product with 89 % catalyst recovery.
Mechanistic Studies on the Michael Addition of Amines and Hydrazines to Nitrostyrenes: Nitroalkane Elimination via a Retro-aza-Henry-Type Process
Kallitsakis, Michael G.,Tancini, Peter D.,Dixit, Mudit,Mpourmpakis, Giannis,Lykakis, Ioannis N.
, p. 1176 - 1184 (2018/02/09)
In this article we report on the mechanistic studies of the Michael addition of amines and hydrazines to nitrostyrenes. Under the present conditions, the corresponding N-alkyl/aryl substituted benzyl imines and N-methyl/phenyl substituted benzyl hydrazones were observed via a retro-aza-Henry-type process. By combining organic synthesis and characterization experiments with computational chemistry calculations, we reveal that this reaction proceeds via a protic solvent-mediated mechanism. Experiments in deuterated methanol CD3OD reveal the synthesis and isolation of the corresponding deuterated intermediated Michael adduct, results that support the proposed slovent-mediated pathway. From the synthetic point of view, the reaction occurs under mild, noncatalytic conditions and can be used as a useful platform to yield the biologically important N-methyl pyrazoles in a one-pot manner, simple starting with the corresponding nitrostyrenes and the methylhydrazine.
Preparation of 5-Aryl-2-Alkyltetrazoles with Aromatic Aldehydes, Alkylhydrazine, Di-tert-butyl Azodicarboxylate, and [Bis(trifluoroacetoxy)iodo]benzene
Imai, Taro,Harigae, Ryo,Moriyama, Katsuhiko,Togo, Hideo
, p. 3975 - 3980 (2016/05/24)
A variety of 5-aryl-2-methyltetrazoles and 5-aryl-2-benzyltetrazoles were directly prepared in good to moderate yields by the reaction of aromatic aldehydes with methylhydrazine and benzylhydrazine, followed by treatment with di-tert-butyl azodicarboxylate and [bis(trifluoroacetoxy)iodo]benzene in a mixture of dichloromethane and 2,2,2-trifluoroethanol at room temperature. The present method is a novel one-pot preparation of 5-aryl-2-methyltetrazoles and 5-aryl-2-benzyltetrazoles through a [2N + 2N] combination under transition metal-free and mild conditions.