Synthesis of .alpha.-cyano carbonyl compounds by flash vacuum thermolysis of (alkylamino)methylene derivatives of Meldrum's acid. Evidence for facile 1,3-shifts of alkylamino and alkylthio groups in imidoylketene intermediates
摘要:
The syntheses and flash vacuum thermolyses of 5-[(alkylamino)methylene]-2,2-dimethyl-1,3-dioxane-4,6-diones (Meldrum's acid derivatives) 13a-i are described. Thermolysis of 13a as well as of ethyl 3-(tert-butylamino)acrylate (22) gives a tautomeric mixture of cyanoacetaldehyde (14) and 3-hydroxypropenenitrile (15). Thermolysis of 13b gives iminoacrolein 26 and not cyanoacetone (29). Thermolysis of 13c,d gives S-methyl cyanothioacetate (30), and 13f-h give cyanoacetamides 31 in high yields. 2-Cyanopent-4-enoic acid derivatives 32 are obtained from Meldrum's acids 13e,i. The results are discussed in terms of facile 1,3-shifts of methylthio and alkylamino groups in imidoylketenes, interconverting imidoylketenes and acylketene imines.
Next-Generation TLC: A Quantitative Platform for Parallel Spotting and Imaging
作者:Alexander A. Boulgakov、Sarah R. Moor、Hyun Hwa Jo、Pedro Metola、Leo A. Joyce、Edward M. Marcotte、Christopher J. Welch、Eric V. Anslyn
DOI:10.1021/acs.joc.0c00349
日期:2020.8.7
developed using a thin-layerchromatography (TLC) imaging method. As a test-bed reaction, we monitored 48 thiol conjugate additions to a Meldrum’s acid derivative (1) in parallel using TLC. The TLC elutions were imaged using a cell phone and a LEGO brick-constructed UV/vis light box. Further, a spotting device was constructed from LEGO bricks that allows simple transfer of the samples from a well-plate
The synthesis of New 5-R-aminoazolo[1,5-a]pyrimidin-7-ones from an N,S-acetal Derivative of Meldrum’s Acid
作者:Daniil N. Lyapustin、Irina V. Marusich、Dilya F. Fayzullina、Evgeny N. Ulomsky、Anatoly I. Matern、Vladimir L. Rusinov
DOI:10.1007/s10593-023-03164-4
日期:——
A one-step method for the synthesis of new 5-aminoazolo[1,5-a]pyrimidines was developed. The use of a synthetic equivalent of carbonyl dielectrophile based on Meldrum's acid made it possible to introduce a substituted amino group into position 5 of azolo[1,5-a]-pyrimidines without the use of severe conditions and palladium catalysts. The tolerance of the reaction to various substituents was also investigated
开发了一种合成新型 5-氨基唑并 [1,5- a ] 嘧啶的一步法。使用基于 Meldrum 酸的合成等价羰基亲电试剂,可以在不使用苛刻条件和钯催化剂的情况下将取代的氨基引入唑并[1,5- a]-嘧啶的5 位。还研究了反应对各种取代基的耐受性。基于分离的中间体,提出了该过程的反应机理。此外,证明了基于获得的化合物合成生物活性分子类似物的可能性。
CHEIKH, ABDELHAMID;BEN;CHUCHE, JOSSELIN;MANISSE, NOEL;POMMELET, JEAN CLAU+, J. ORG. CHEM., 56,(1991) N, C. 970-975
作者:CHEIKH, ABDELHAMID、BEN、CHUCHE, JOSSELIN、MANISSE, NOEL、POMMELET, JEAN CLAU+