Preparation of New Nitrogen-Bridged Heterocycles. 43.1 Synthesis and Reaction of 5aH-Pyrido[1,2-d][1,3,4]thiadiazepine Derivatives
摘要:
Reactions of some 1-pyridinio- and 1-(4-methylpyridinio)(arenethiocarbonyl) with dimethyl acetylenedicarboxylate in chloroform afforded neither the expected dimethyl 2-aryl-5aH-pyrido-[1,2-d][1,3,4]thiadiazepine-4,5-dicarboxylates nor their intramolecular Diels-Alder adducts, but gave novel rearranged products, dimethyl 4-aryl-5-thia-2,3-diazatricyclo[4.3.2.0(2,7)]undeca-3,8,10-triene-6,11-dicarboxylates in low to moderate yields. On the other hand, similar reactions of 1-(3-methylpyridinio)- and 1-(2-methylquinolinio)(arenethiocarbonyl)amidates with the same reagent provided 1:1 primary adducts, dimethyl 2-aryl-6-methyl-5aH-pyrido[1,2-d][1,3,4]thiadiazepine-4,5-dicarboxylates and dimethyl 2-aryl-5a-methyl-5aH-[1,3,4]thiadiazepino[4,5-alpha]quinoline-4,5-dicarboxylates, respectively.
Pyridinium-, 2-methylpyridinium-, and 2,6-dimethylpyridinium-1-thioacylaminides (5–7) were prepared from the corresponding unsubstituted pyridinium-1-aminides and methyl dithiocarboxylates in fairly good yields. The alkylation reaction of 5–7 took place exclusively on the thiocarbonyl sulfur, yielding pyridinium salts in quantitative yields. The NMR spectroscopic studies indicated that E and Z forms existed for these pyridinium salts. The thermal decomposition of 5–7 yielded the corresponding pyridine, nitrile, and sulfur in good yields.
以相应的未取代的吡啶-1-酰胺和二硫代羧酸甲酯为原料,制备了吡啶-1-酰胺、2-甲基吡啶-1-酰胺和 2,6-二甲基吡啶-1-硫代羧酸酰胺(5-7),收率相当高。5-7 的烷基化反应完全发生在硫代羰基硫上,定量生成吡啶鎓盐。核磁共振光谱研究表明,这些吡啶鎓盐存在 E 和 Z 两种形式。5-7 的热分解产生了相应的吡啶、腈和硫,收率很高。
Preparation of New Nitrogen-Bridged Heterocydes. 18. Facile Formations of 3-Arylpyrazolo[1,5-<i>a</i>]pyridines and 1-Arylindolizines
benzylthio)methyleneamino]pyridinium and 1-[2-(substituted benzylthio)vinyl]pyridinium bromides possessing an electron-withdrawing substituent such as a nitro or cyano group in the presence or absence of a dehydrogenating agent afforded the corresponding 3-arylpyrazolo[1,5-a]pyridines and 1-arylindolizines in moderate to good yields, while the reactions of the parent pyridiniumsalts and those having an