(2R,2'S)-2,2'-Bi-piperidine-1,1'-diium dibromide.
The title compound, C10H22N2 (2+)·2Br(-), was synthesized via reduction of 2,2'-dipyridyl with Ni-Al alloy/KOH, followed by separation of diastereoisomers (meso and rac) by recrystallization from ethanol. Although the two bridging C atoms are optically active, these two chiral centers adopt an (S,R) configuration; thus, the title compound contains an achiral meso form of 2,2'-bi-piperidine. Both of the piperidinium rings adopt chair conformations, and the two N atoms are trans to each other; an inversion center is located in the mid-point of the central C-C bond. The conformation of the organic moiety resembles that of 1,1'-bi(cyclo-hexa-ne). The organic di-ammonium cations are linked to each other through hydrogen bonding with bromide counter-ions, each of which forms two hydrogen bonds (N-H⋯Br) with two adjacent organic cations, thus linking the latter together in sheets parallel to (100).
Department of Chemistry, Tufts University, 62 Talbot Ave., Medford, MA 02155, USA.
Guang
G
Yang
Bruker AXS Inc., 5465 E. Cheryl Parkway, Madison, WI 53711, USA.
Bruce C
BC
Noll
Department of Chemistry, Tufts University, 62 Talbot Ave., Medford, MA 02155, USA.
Elena V
EV
Rybak-Akimova