L-LeucineL-leucinium picrate

Abstract

The asymmetric unit of the title compound, C6H13NO2·C6H14NO2+·C6H2N3O7−, contains two unprotonated leucine residues, two protonated leucinium cations and two picrate anions. The leucine residues show a class II hydrogen‐bonding scheme and the leucinium residues show a class I hydrogen‐bonding scheme. The leucine and leucinium residues form infinite hydrogen‐bonded chains running along the a axis.

l-serine picrates

“…6). However, examination of the IR spectra in Figs 5,6 shows that in the 1200-700 cm -1 range there is additional absorption in Fig. 6 compared to Fig.…”

“…In addition to simple picrate salts there are also picrates of some amino acids with A…A + type dimeric cation. Such salts are known for glycine (see [3] and references therein), β-alanine [4], L-alanine [5], Lleucine [6], L-tryptophan [7], DL-phenylalanine [8] and DL-methionine [9].…”

Optical investigation of L-leucine L-leucinium picrate

“…In summary, the compound crystallizes in the triclinic system with the non centrosymmetric space group P1 (Z=2) with a = 7.132(5)Å, b = 11.799(9)Å, c = 15.372(2)Å,  = 106.61(6)°,  = 95.32(6)° and  = 90.97(7)°. From the single crystal XRD data, the structure is stabilized by an extensive network of O-H…O and N-H…O hydrogen bonds [21].…”

“…Structural features at room temperature have been mentioned elsewhere [21]. In summary, the compound crystallizes in the triclinic system with the non centrosymmetric space group P1 (Z=2) with a = 7.132(5)Å, b = 11.799(9)Å, c = 15.372(2)Å,  = 106.61(6)°,  = 95.32(6)° and  = 90.97(7)°.…”

“…In conjunction with some current research works on these amino acids picrate, our last two published papers have been devoted to the X-ray powder diffraction, vibrational studies and DFT calculations as well as electrical and dielectrical study of the organic compound LLeucine L-Leucinium Picrate (LLLLP) [19,20]. Structural studies, second harmonic generation SHG and thermal analysis of LLLLP were investigated earlier [13,21]. However, few optical studies of this kind of materials have been reported while much effort has been placed on determining structural properties.…”