Reactivity of sarcosine and 1,3-thiazolidine-4-carboxylic acid towards salicylaldehyde-derived alkynes and allenes
作者:Fernanda M. Ribeiro Laia、Clara S.B. Gomes、Teresa M.V.D. Pinho e Melo
DOI:10.1016/j.tet.2013.09.052
日期:2013.11
The reaction of sarcosine and 1,3-thiazolidine-4-carboxylic acid with salicylaldehyde-derived alkynes and allenes opened the way to new chromeno[4,3-b]pyrrole and chromeno[2,3-b]pyrrole derivatives. Tetrahydro-chromeno[4,3-b]pyrroles were obtained from the reaction of these secondary aminoacids with O-propargylsalicylaldehyde. Interestingly, sarcosine reacted with ethyl 4-(2-formylphenoxy)but-2-ynoate
肌氨酸和1,3-噻唑烷-4-羧酸与水杨醛衍生的炔烃和丙二烯反应打开了通向新色烯并[4,3- b ]吡咯并色烯并[2,3- b ]吡咯衍生物。四氢色烯并[4,3- b从这些仲氨基酸与反应获得]吡咯ö -propargylsalicylaldehyde。有趣的是,肌氨酸用乙酸乙酯反应4-(2-甲酰基苯氧基)丁-2-炔酸甲酯,得到单环吡咯从初始形成的1,3-偶极环加成的重排得到。4-(2-甲酰基苯氧基)丁-2-炔酸甲酯与1,3-噻唑烷-4-羧酸在立体选择性方式得到预期色烯并吡咯并脱羧缩合[1,2 Ç]噻唑,其结构是由明确的X射线晶体学确定。然而,1 ħ,3 ħ吡咯并[1,2- c ^ ]距离吡喃环的开口得到的噻唑也被分离。与反应ö -丁-2,3-二烯基水杨醛,得到3-亚甲基hexahydrochromeno [4,3- b ]吡咯。ø -Allenyl水杨醛与肌氨酸和1,3-噻唑烷-4-羧酸反应
Visible-light-induced phenylchalcogenyl-oxygenation of allenes having aryl or electron withdrawing substituents with ambient air as a sole oxidant
The synthesis of regio- and stereoselective arylsubstitutedα,β-unsaturated aldehydes and ketones from activated allenes was achieved. This mild and non-metallic oxidation is exclusively driven by benign ambient air and triggered by visible light. The same starting materials under ideal anaerobic conditions led to the 2,3-diphenylselenation adduct with no trace of oxygenated products, demonstrating
ymé (GBB) reaction for the synthesis of spiro[chromene-imidazo[1,2-a]pyridin]-3′-imine was discovered. The unusual transformation represents the first example of activation and the reaction of the imidazole carbon atom. In this postcondensational modification, KOt-Bu acts as a base, which, after the isomerization of an alkyne moiety to allene, causes the next unique nucleophilic reaction of the imidazole
发现了用于合成螺[色烯-咪唑并[1,2- a ]吡啶]-3'-亚胺的Groebke-Blackburn-Bienaymé(GBB)反应的无过渡金属后修饰。这种不寻常的转变代表了咪唑碳原子活化和反应的第一个例子。在这种后缩合修饰中,KO t -Bu 作为碱,在炔部分异构化为丙二烯后,引起咪唑碳原子的下一个独特亲核反应,从而产生螺环结构。基于DFT计算证实了所提出的反应机理。
Intramolecular [3+2]-cycloaddition of nitrones with allenes and alkynes
作者:Albert Padwa、Michael Meske、Zhijie Ni
DOI:10.1016/s0040-4039(00)60672-x
日期:1993.8
The intramolecular dipolar cycloaddition reactions of allenyl and alkynyl nitrones proceed smoothly to give high yields of cycloadducts.