The reduction of 2,6-diaminoanthraquinone to 2,6-diaminoanthracene was examined under a variety of conditions. Direct reduction using zinc powder gave a mixture of the target product and 9,10-dihydro-2,6-diaminoanthracene under all the conditions examined. Protection of the starting amine, followed by borohydride reduction and deprotection, gave the target product in 14–50% yield. Finally, tin powder was used to reduce the anthraquinone to 2,6-diaminoanthrone in quantitative yield. This compound was further reduced to the target 2,6-diaminoanthracene in 55–65% yield.

中文翻译：

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一种优化的2,6-二氨基蒽的合成方法

在多种条件下检查了2，6-二氨基蒽醌向2，6-二氨基蒽的还原。在所有检查的条件下，使用锌粉直接还原得到目标产物和9,10-二氢-2,6-二氨基蒽的混合物。保护起始胺，然后进行硼氢化物还原和脱保护，以14-50％的收率得到目标产物。最后，使用锡粉以定量收率将蒽醌还原为2,6-二氨基蒽酮。将该化合物进一步还原为目标2,6-二氨基蒽，产率为55-65％。