SEMMELWEIS UNIVERSITY PETER PAMANY CATLIC UNIVERSITY Development of Complex Curricula for Molecular Bionics and Infobionics Programs within a consortial* framework** Consortium leader PETER PAMANY CATLIC UNIVERSITY Consortium members SEMMELWEIS UNIVERSITY, DIALG CAMPUS PUBLISER The Project has been realised with the support of the European Union and has been co-financed by the European Social Fund *** **Molekuláris bionika és Infobionika Szakok tananyagának komplex fejlesztése konzorciumi keretben ***A projekt az Európai Unió támogatásával, az Európai Szociális Alap társfinanszírozásával valósul meg. 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 1
rganic and Biochemistry (Szerves és Biokémia ) Isomerism: 2D and 3D. Configuration, conformation; 3D representation (Izoméria: 2D és 3D nézetben. Konfiguráció, konformáció; térbeli ábrázolás) Compiled by dr. Péter Mátyus with contribution by dr. Gábor Krajsovszky Formatted by dr. Balázs Balogh 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 2
Table of Contents Isomerism 4 8 Stereochemistry 9 16 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 3
Types of isomerism Two compounds are with the same general formula their structures are the same yes Are they superimposable on each other? not they are isomeric structures? 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 4
yes Is their connectivity different? not the compounds are constitutional isomers the compounds are stereoisomers Enantiomers yes Is their relationship the same as an object and its nonidentical mirror-image? not Diastereomers Are they superimposable by simple rotation around a single bond? yes not Conformational Configurational enantiomers enantiomers Are they superimposable by simple rotation around a single bond? yes not Conformational diastereomers Configurational diastereomers 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 5
CNSTITUTINAL ISMERISM STEREISMERISM Configurational isomerism Conformational isomerism 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 6
Isomerism 1. Constitutional isomers These compounds possess the same molecular formula, but the connectivity of atoms is different. Different 2D structures 2. Stereoisomers These compounds possess the same general formula and connectivity, they differ in the spatial arrangement of their atoms/groups. Different 3D structures Enantiomers: nonsuperimposable mirror-images of each other Diastereomers: stereoisomers but not with enantiomeric relationship (not mirror-images of each other) 9/14/2011. TÁMP 4.1.2-08/2/A/KMR-2009-0006 7
1 2 3 C C 2 C 2 n-butane 3 C C 2 C 2 n-butyl 3 C C C 2 sec-butyl 1 3 3 C C C 2 3 C C isobutane C 3 isobutyl C tert-butyl 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 8
Stereochemistry The difference in properties of isomers is due to the difference in the relative arrangements of various atoms or groups present in their molecules. Configuration: A particular spatial arrangement of atoms, usually disregarding the rotation around the single bonds. Conformation: A particular arrangement that originates from rotation around the single bonds. 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 9
- stretching r 1 r 2 r 3 - bending - torsion α τ(φ) 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 10
bending E stretching + + E dissociation ~90 ~50 kcal/mol ~30 kcal/mol r α 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 11
Newman projection: τ (torsional angle) ~10 kcal/mol ~1 kcal/mol 0 60 120 180 240 300 360 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 12
Y C 2 C 2 Y = = ethane Y = = n-butane Y Y Y Y Y Y Y 0 60 120 180 240 300 360 clockwise -360-300 -240-180 -120-60 0 counterclockwise 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 13
E(Θ) minimum 1/2 M M M 1/2 M m m m 0 60 120 180 240 300 360 Θ 3 C M = m MAXIMUM 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 14
Y 0 Y Y Y Y Y Y 60 120 180 240 300 360 anti effect gauche effect 3 C extreme gauche effect 0 60 120 180 240 300 360 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 15
E (kcal) 5.8 2.9 C 3 3 C 0.7 0 60 120 180 240 300 360 dihedral angle 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 16
ΔG = G ΔG K = e 1 G ΔG RT ΔG = RTlnK = Δ TΔS ΔS = 0.74 ΔS = 2K = 1.9 G Gibbs free energy enthalpy S entropy T temperature R gas contans K equilibrium constant 2 Gibbs free energy is the enthalpy minus the product of thermodynamic temperature and entropy. It was formerly called free energy or free enthalpy. Entropy is the quantity the change in which is equal to the heat brought to the system in a reversible process at constant temperature divided by that temperature. Enthalpy is the internal energy of a system plus the product of pressure and volume. Its change in a system is equal to the heat brought to the system at constant pressure. 2011.09.14.. TÁMP 4.1.2-08/2/A/KMR-2009-0006 17