Question

what is le-bell van't hoff model?

Answer 1

Inorganic chemistry, theLe Bel–van't Hoffrulestates that the number ofstereoisomersof an organic compound containing no internalplanes of symmetryis 2n, where n represents the number ofasymmetric carbonatoms.Joseph Achille Le Bel[1]andJacobus Henricus van 't Hoff[2]both announced this hypothesis in 1874 and that this accounted for all molecular asymmetry known at the time.[3]As an example, four of the carbon atoms of thealdohexoseclass of molecules are asymmetric, therefore the Le Bel-van't Hoffrule gives a calculation of 24=16 stereoisomers. This is indeed the case: these chemicals are twoenantiomerseachof eight differentdiastereomers:allose,altrose,glucose,mannose,gulose,idose,galactose, andtalose.Four asymmetric carbon atoms in glucose (the four carbon–oxygen bonds marked in red)References1.^Le Bel, Joseph Achille (1874)."Sur les relations qui existent entre les formules atomiques des corps organiques et le pouvoir rotatoire de leurs dissolutions"[On the relations that exist between the atomic formulas of organic substances and the rotatory power of their solutions].Bulletin de la Société Chimique de Paris(in French).22: 337–347.2.^van 't Hoff, Jacobus Henricus (1874)."Sur les formules de structure dans l'espace"[Onstructural formulas in space].Archives Néerlandaises des Sciences Exactes et Naturelles(in French).9: 445–454.3.^"Le Bel-van't Hoff rule". TheFreeDictionary's Medical dictionary.