Britvin Sergey N, Rumyantsev Andrey M
Department of Crystallography, Saint-Petersburg State University, Universitetskaya Nab. 7/9, 199034 St. Petersburg, Russian Federation.
Department of Genetics and Biotechnology, Saint-Petersburg State University, Universitetskaya Nab. 7/9, 199034 St. Petersburg, Russian Federation.
Acta Crystallogr E Crystallogr Commun. 2017 Nov 17;73(Pt 12):1861-1865. doi: 10.1107/S2056989017015870. eCollection 2017 Dec 1.
The cage of 2,5-di-aza-bicyclo-[2.2.1]heptane is frequently employed in synthetic chemistry as a rigid bicyclic counterpart of the piperazine ring. The 2,5-di-azabicyclo-[2.2.1]heptane scaffold is incorporated into a variety of compounds having pharmacological and catalytic applications. The unsubstituted parent ring of the system, 2,5-di-aza-bicyclo-[2.2.1]heptane itself, has not been structurally characterized. We herein report on the mol-ecular structure of the parent ring in (1,4)-2,5-diazo-niabi-cyclo-[2.2.1]heptane dibromide, CHN·2Br. The asymmetric unit contains two crystallographically independent cages of 2,5-di-aza-bicyclo-[2.2.1]heptane. Each cage is protonated at the two nitro-gen sites. The overall charge balance is maintained by four crystallographically independent bromide ions. In the crystal, the components of the structure are linked a complex three-dimensional network of N-H⋯Br hydrogen bonds.
2,5-二氮杂双环-[2.2.1]庚烷的笼状结构在合成化学中经常被用作哌嗪环的刚性双环类似物。2,5-二氮杂双环-[2.2.1]庚烷骨架被引入到多种具有药理和催化应用的化合物中。该体系未被取代的母体环，即2,5-二氮杂双环-[2.2.1]庚烷本身，其结构尚未得到表征。我们在此报告(1,4)-2,5-二氮杂双环-[2.2.1]庚烷二溴化物CHN·2Br中母体环的分子结构。不对称单元包含两个晶体学独立的2,5-二氮杂双环-[2.2.1]庚烷笼状结构。每个笼状结构在两个氮位点处被质子化。整体电荷平衡由四个晶体学独立的溴离子维持。在晶体中，结构组分通过N-H⋯Br氢键连接成一个复杂的三维网络。
