TY - JOUR

T1 - New 1

T2 - 1 and 2:1 salts in the ' dl -norvaline-maleic acid' system as an example of assembling various crystal structures from similar supramolecular building blocks

AU - Arkhipov, Sergey G.

AU - Losev, Evgeniy A.

AU - Boldyreva, Elena V.

PY - 2017/1/1

Y1 - 2017/1/1

N2 - Molecular salts and cocrystals of amino acids have potential applications as molecular materials with nonlinear optical, ferroelectric, piezoelectric, and other various target physical properties. The wide choice of amino acids and coformers makes it possible to design various crystal structures. The amino acid-maleic acid system provides a perfect example of a rich variety of crystal structures with different stoichiometries, symmetries and packing motifs built from the molecular building blocks, which are either exactly the same, or differ merely by protonation or as optical isomers. The present paper reports the crystal structures of two new salts of the dl-norvaline-maleic acid system with 1:1 and 2:1 stoichiometries, namely dl-norvalinium hydrogen maleate, C5H12NO2 +·C4H3O4 -, (I), and dl-norvalinium hydrogen maleate-dl-norvaline, C5H12NO2 +·C4H3O4 -·C5H11NO2, (II). These are the first examples of molecular salts of dl-norvaline with an organic anion. The crystal structure of (I) has the same C2 2(12) structure-forming motif which is common for hydrogen maleates of amino acids. The structure of (II) has dimeric cations. Of special interest is that the single crystals of (I) which are originally formed on crystallization from aqueous solution transform into single crystals of (II) if stored in the mother liquor for several hours.The crystals of two new salts in the dl-norvaline-maleic acid system provide examples of different molecular packing of the molecular building blocks, which are either the same, or differ merely by protonation.

AB - Molecular salts and cocrystals of amino acids have potential applications as molecular materials with nonlinear optical, ferroelectric, piezoelectric, and other various target physical properties. The wide choice of amino acids and coformers makes it possible to design various crystal structures. The amino acid-maleic acid system provides a perfect example of a rich variety of crystal structures with different stoichiometries, symmetries and packing motifs built from the molecular building blocks, which are either exactly the same, or differ merely by protonation or as optical isomers. The present paper reports the crystal structures of two new salts of the dl-norvaline-maleic acid system with 1:1 and 2:1 stoichiometries, namely dl-norvalinium hydrogen maleate, C5H12NO2 +·C4H3O4 -, (I), and dl-norvalinium hydrogen maleate-dl-norvaline, C5H12NO2 +·C4H3O4 -·C5H11NO2, (II). These are the first examples of molecular salts of dl-norvaline with an organic anion. The crystal structure of (I) has the same C2 2(12) structure-forming motif which is common for hydrogen maleates of amino acids. The structure of (II) has dimeric cations. Of special interest is that the single crystals of (I) which are originally formed on crystallization from aqueous solution transform into single crystals of (II) if stored in the mother liquor for several hours.The crystals of two new salts in the dl-norvaline-maleic acid system provide examples of different molecular packing of the molecular building blocks, which are either the same, or differ merely by protonation.

KW - amino acid salt

KW - crystal engineering

KW - crystal structure

KW - dl -norvaline

KW - hydrogen bond

KW - maleic acid

KW - L-HISTIDINE

KW - L-PHENYLALANINIUM MALEATE

KW - MEDIATED POLYMORPHIC TRANSFORMATION

KW - HYDROGEN MALEATE

KW - L-ALANINIUM MALEATE

KW - AMINO-ACIDS

KW - L-ARGININE

KW - GROWTH

KW - DL-norvaline

KW - X-RAY

KW - 150 K

UR - http://www.scopus.com/inward/record.url?scp=85007605305&partnerID=8YFLogxK

U2 - 10.1107/S2053229616018271

DO - 10.1107/S2053229616018271

M3 - Article

C2 - 28035097

AN - SCOPUS:85007605305

VL - 73

SP - 13

EP - 19

JO - Acta Crystallographica Section C: Structural Chemistry

JF - Acta Crystallographica Section C: Structural Chemistry

SN - 2053-2296

IS - 1

ER -