Structures of Addition Products of Acetylenedicarboxylic Acid Esters with Various Dinucleophiles. An application of C, H-spin-coupling constants
作者:Ulrich Vögeli、Wolfgang von Philipsborn、Kuppuswamy Nagarajan、Mohan D. Nair
DOI:10.1002/hlca.19780610207
日期:1978.3.8
Heterocyclic compounds obtained by addition of acetylenedicarboxylicacidesters to thioureas, cyclic amidines and o-difunctionalized aromatic systems have been studied by 13C-NMR. In particular, C, H-spin-coupling constants over two and three bonds were used to differentiate between the various constitutional isomers and to establish the configuration of trisubstituted exocyclic C, C-double bonds
Hydroamination Reactions of Alkynes with<i>ortho</i>-Substituted Anilines in Ball Mills: Synthesis of Benzannulated N-Heterocycles by a Cascade Reaction
electrophilic alkynes and anilines with OH, NH, or SH groups in the ortho position. For the heterocycle formation, it was shown that several stress conditions were able to initiate the reaction in the solid state. Processing in a ball mill seemed to be advantageous over comminution with mortar and pestle with respect to process control. In the latter case, significant postreaction modification occurred during
Microwave-Assisted Synthesis of Quinoxalines, Benzoxazines, and Benzothiazines Under Solvent-Free Conditions
作者:Majid M. Heravi、Navabeh Nami、Hossien A. Oskooie、Rahim Hekmatshoar
DOI:10.1080/104265090889585
日期:2005.8.1
The addition of dialkyl acetylenedicarboxylate to o-phenylenediamine, o-aminophenol, and o-aminothiophenol under microwave it-radiation in solventless System rapidly afforded quinoxaline, benzoxazine, and benzothiazine derivatives, respectively.