A superior synthetic route to 4,4′-diamino-2,2′-bipyridine has been developed. This procedure compares favorably with existing methods, producing 4 times the yield previously reported. In addition, mild reaction conditions are utilized, allowing a considerably more efficient production, and subsequent purification, of the diamino complex.

中文翻译：

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由4,4'-二硝基-2,2'-联吡啶-N，N'-二氧化物改进的4,4'-二氨基-2,2'-联吡啶的合成

已经开发出一种高级的合成4,4'-二氨基-2,2'-联吡啶的途径。该方法与现有方法相比具有优势，其产量是先前报道的4倍。另外，利用了温和的反应条件，使二氨基配合物的生产和随后的纯化大大提高了效率。