The synthetic chemistry of the relatively unknown pyridazino [4,5-d]pyridazine ring system has been extended. 1,4-Diaminopyridazino [4,5-d]pyridazine (VIII) has been prepared by two routes, the most interesting of these being the one-step conversion of 4,5-dicyanopyridazine into VIII with hydrazine. Upon nitration VIII gave only the mononitramine (X). Attempts to prepare 1,4-dichloropyridazino [4,5-d]pyridazine gave only 4-chloro-2H-pyridazino [4,5-d]pyridazin-1-one (XII). Pyrimido [4,5-d]pyridazine-1,3-dione (XIV) was prepared from pyridazine-4,5-dicarboxamide (IV). The hydrolysis of 5,8-dichloropyrazino [2,3-d]pyridazine (XV) gave 5-chloropyrazino [2,3-d]pyridazin-8-one (XVII) and likewise the ammonolysis of XV gave 5-amino-8-chloropyrazino [2,3-d]pyridazine (XX). As expected the hydrolysis of 5,8-dibromo-pyrazino [2,3-d]pyridazine (XXI) gave 5-bromopyrazino [2,3-d]pyridazin-8-one (XXII). Attempted catalytic dechlorination of 5-chloropyrazino [2,3-d]pyridazin-8-one (XVII) gave 1,2,3,4-tetrahydropyrazino [2,3-d]pyridazin-5-one (XIX).

中文翻译：

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哒嗪并[4,5- d ]哒嗪，吡嗪并[2,3- d ]哒嗪和嘧啶并[4,5- d ]哒嗪的合成

相对未知的哒嗪并[4,5- d ]哒嗪环系统的合成化学得到了扩展。1,4-二氨基哒嗪[4,5- d ]哒嗪（VIII）已通过两种途径制备，其中最有趣的是将4,5-二氰基哒嗪与肼一步转化为VIII。硝化后，VIII仅给出单硝胺（X）。尝试制备1，4-二氯哒嗪[4，5- d ]哒嗪仅得到4-氯-2 H-哒嗪[4，5 - d ]哒嗪-1-酮（XII）。由哒嗪-4,5-二甲酰胺（IV）制备嘧啶[4,5 - d ]哒嗪-1,3-二酮（XIV）。5,8-二氯吡嗪并[2,3- d ]哒嗪（XV）的水解得到5-氯吡嗪并[2,3-d ]哒嗪-8-一（XVII），同样通过XV的氨解得到5-氨基-8-氯吡嗪并[2，3- d ]哒嗪（XX）。如所预期的，5，8-二溴-吡嗪并[2，3- d ]哒嗪（XXI）的水解得到5-溴吡嗪并[2，3 - d ]哒嗪-8-一（XXII）。尝试对5-氯吡嗪并[2,3- d ]哒嗪-8-（XVII）进行催化脱氯，得到1,2,3,4-四氢吡嗪并[2,3 - d ]哒嗪-5-one（XIX）。