C19H25N3O4S2, orthorhombic, P2i2,2i (No. 19), a = 6.396 (1)
Source of materialThe title compound was obtained from the corresponding azide [1] by hydrogénation (in DMF, Pd (10 %)/C, 4 bar, 298 K). The solid amine was precipitated by adding H2O and single crystals were grown by slow cooling of a hot DMSO solution of the title compound to room temperature.
Experimental detailsPositions of the H(-C) hydrogen atoms were calculated (riding model) with U\so fixed at 1.2i/eq of the corresponding carbon atom. The hydrogen atoms of the amino group (N3) could not be located and were not considered. One of the methyl groups (C11 ) proved to be disordered and was refined with two positions (C 11 a and CI lb) having site occupancies of each 50 %.
Discussion1,4-Diazepane-6-amine could serve as an interesting, facially coordinating complexing agent for divalent transition metal cations [2], and the title compound was therefore prepared in our laboratory as an intermediate within the synthesis of this ligand. The seven-membered 1,4-diazepane ring adopts an approximate twist-chair (TC) conformation which is very similar to the conformation observed for the azide precursor [ 1 ], with an axial orientation of the amino group, a comparatively short C3-C4 bond of 145.9(7) pm, and a significantly flattened pyramidal geometry around the two ring nitrogen atoms (sum of bond angels around N1 and N2: 351.6° and 352.0°, respectively). The two S-Ν bonds with bond distances of 161.8(4) pm and 162.8(4) pm are again slightly shorter than a regular Ν-S single bond.