Naslov
Crystal structure and conformational analysis of 1-[N-(tert-butoxycarbonyl)amino]-2-hydroxymethylcyclopropane-1-carboxylic acid

Autori
Cetina, Mario ; Hergold-Brundić, Antonija ; Raos, Nenad ; Žuža-Mak, Lora

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
XVIII. hrvatski skup kemičara i kemijskih inženjera / Zrnčević, Stanka - Zagreb : Hrvatsko društvo kemijskih inženjera i tehnologa (HDKI) ; Hrvatsko kemijsko drustvo ; Hinus, 2003, 71-71

ISBN
953-6894-08-4

Skup
XVIII. hrvatski skup kemičara i kemijskih inženjera

Mjesto i datum
Zagreb, Hrvatska, 16.02.2003. - 19.02.2003

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
crystal structure; 1-amino-1-carboxylic acid derivatives; hydrogen bonds; conformation analysis

Sažetak
The compound crystallizes as centrosymmetric hydrogen bonded R22(8) dimer with O1...O2 distance of 2.621(3) Å and O1-H...O2 angle of 176(1)o. The carboxyl dimer exists in a state of disorder [C-O bonds in the carboxyl group are equal in length: C4-O2 = 1.264(2) ; C4-O1 = 1.258(3) Å]. In the crystal structure was also observed the intramolecular H-bond O5...O3 [2.750(2) Å ; 157(3)o], and intermolecular H-bond N1...O5 [2.874(3) Å ; 174(2)o] forming infinite chain along the b axis. The intermolecular H-bond C2...O2 [3.395(3) Å ; 143(1)o] forms ten-membered ring of R22(10) type, which geometry centre coincides with a crystallographic centre of inversion. The molecules are additionally connected by very weak intermolecular hydrogen bond C3...O3 [3.501(3) Å ; 165(1)o]. By using the model of overlapping spheres (OS method) for finding the low-energy conformations [1] 25 conformations of the title compound were obtained from the initial structure (minimized crystal conformation). The energy of the initial conformation is 1.2 kJ mol-1 above the lowest energy conformation, and 15.1 kJ mol-1 below the highest energy conformation. The crystal and initial conformation differ in the position of the carboxylic group (3.3° and 77.9°, respectively, for O1-C4-C1-N1), while the other torsion angles do not differ significantly (the maximal difference is 21.1°). [1] Raos, N., J. Comput. Chem. 21 (2000) 1353.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

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