Two-Step Synthesis of 3,4-Dihydropyrrolopyrazinones from Ketones and Piperazin-2-ones
作者:Cosme Sandoval、Ngiap-Kie Lim、Haiming Zhang
DOI:10.1021/acs.orglett.8b00197
日期:2018.2.16
An expedient two-stepsynthesis of 3,4-dihydropyrrolopyrazinones has been achieved via a Vilsmeier–Haack reaction of ketones, followed by an annulation of the corresponding chloroaldehydes with commercially available piperazin-2-ones. A variety of cyclic and acyclic ketones and piperazin-2-ones participated in this two-step chemistry, affording the desired 3,4-dihydropyrrolopyrazinones in up to 78%
2-Sulfonylpyridine derivatives can be industrially produced efficiently by reacting a sulfonyl cyanide derivative with an &agr;,&bgr;-unsaturated carbonyl compound and a 2-{[(2-pyridyl)methyl]thio}-1H-benzimidazole skeleton can be formed in one step in a good yield by reacting this type of the 2-sulfonylpyridine derivative with a 2-methylthio-1H-benzimidazole derivative in the presence of an organolithium compound.
Efficient Synthesis of 4- and 5-Substituted 2-Aminopyrimidines by Coupling of β-Chlorovinyl Aldehydes and Guanidines
作者:Anna S. Komendantova、Alexander V. Komkov、Yulia A. Volkova、Igor V. Zavarzin
DOI:10.1002/ejoc.201700737
日期:2017.8.10
A general, practical and simple synthesis of functionalized 2-aminopyrimidines starting from β-chlorovinyl aldehydes and amidines is reported. In the presence of potassium carbonate, various ketones have been efficiently incorporated into the pyrimidine derivatives by two-step sequence involving the Vilsmeier-Haack reaction followed by the condensation with guanidines. The protocol is distinguished
Reactions of hydrazones derived from oxamic acid thiohydrazides
作者:Yulia A. Volkova、Elena I. Chernoburova、Albina S. Petrova、Alexander A. Shtil、Igor V. Zavarzin
DOI:10.1080/10426507.2016.1250759
日期:2017.2.1
ABSTRACT This brief review describe the recent advances in using oxamic acid thiohydrazides as precursors for the formation of hydrazones intermediates from natural and synthetic compounds bearing a carbonyl group. These intermediates undergo a variety of synthetically useful transformations, which include nucleophilic addition and 6π-electrocyclic reactions to generate new heterocycles.
A one-pot synthesis of new variously substituted γ-chloro-γ, β-allylic carbamates have been carried out starting from β-chloro-α, β-unsaturated aldehydes. The new carbamates and the corresponding intermediates, the γ-chloro-γ, β-allylic alcohols, were fully characterized by (1H and 13C) NMR, IR and HRMS spectroscopic techniques. The crystal structures of two allylic carbamates, were established by
已经从 β-氯-α, β-不饱和醛开始一锅合成新的各种取代的 γ-氯-γ, β-烯丙基氨基甲酸酯。新型氨基甲酸酯和相应的中间体 γ-氯-γ、β-烯丙醇通过 ( 1 H 和13 C) NMR、IR 和 HRMS 光谱技术进行了全面表征。通过单晶 X 射线衍射确定了两种烯丙基氨基甲酸酯的晶体结构。