3-[4-(3-Aminopropyl)piperazin-1-yl]propan-1-aminium chloride

The title compound, C10H25N4+·Cl−, contains monoprotonated amine cations and chloride anions. The cations form chains along the [101] direction via N—H⋯N bonds, while N—H⋯Cl hydrogen bonds link the anions and cations into a three-dimensional structure.

The title compound, C 10 H 25 N 4 + ÁCl À , contains monoprotonated amine cations and chloride anions. The cations form chains along the [101] direction via N-HÁ Á ÁN bonds, while N-HÁ Á ÁCl hydrogen bonds link the anions and cations into a three-dimensional structure.

Comment
In solvothermal synthesis, organic amines are generally used as structure-directing agents, and it is known that sometimes salts of the amines appear as unwanted side products. However, recent work on the solvothermal synthesis of phosphates (Rao et al., 2000) and sulfates (Behera et al., 2004) suggests that these amine salts might play a role in the formation of open-framework phases. It has also been found that the use of amine salts as sources of structure-directing agents may result in the formation of new open-framework structures.
In the title compound, C 10 H 25 N 4 + ÁCl À , (I), which was the unexpected product of a solvothermal reaction, the amine 1,4bis(3-aminopropyl)piperazine (bapp) crystallizes as a monoprotonated cation, H + bapp, accompanied by a charge-balancing chloride anion (Fig. 1). As well as electrostatic forces, the anions and cations in (I) interact by means of hydrogen bonds ( Table 1). The H + bapp cations are connected by strong N-HÁ Á ÁN hydrogen bonds, forming infinite chains that run along the [101] direction. The chains are cross-linked by N-HÁ Á ÁCl bonds arising from the terminal -NH 2 and -NH 3 + groups to form layers parallel to the ac plane (Fig. 2). Further N-HÁ Á ÁCl hydrogen bonds link the layers into a three-dimensional structure (Fig. 3). View of (I), showing 50% probability displacement ellipsoids (arbitrary spheres for the H atoms).

Experimental
A mixture of CuCl (2 mmol), Te (1 mmol) and 1,4-bis(3-aminopropyl)piperazine (4.2 ml) was loaded into a 23 ml Teflon-lined steel autoclave, heated for 13 days at 473 K and then cooled to room temperature over a period of 12 h. The product, consisting of hygroscopic colourless needles of (I) and a black powder, was filtered and washed with methanol and acetone.
H atoms were located in difference maps and their positions were freely refined; U iso (H) = 1.2U eq (carrier).
The author thanks the UK EPSRC for an Advanced Research Fellowship. View of a layer parallel to the (010) plane, showing the network of hydrogen bonds (dashed lines). Hydrogen atoms not participating in hydrogen bonding have been omitted for clarity.

Figure 3
View of the packing in (I). Drawing conventions as in Fig. 2