Question

1. a) (2 points) The Fisher projection of molecule A reveals that it has three chiral carbons. What is the maximum number of stereoisomers that a molecule with three chiral carbons can have? b) (18 points) Even though molecule A has three chiral carbon atoms, there are only four stereoisomers: A, B, C, and D. Explain why so few stereoisomers exist, using structures as part our answer. Your answer should take your answer to a) into account. CH,OH CH2OH CH OH CH OH нонн нннон Антон нон Нонн но -н ньон HOH нон H- OH HOH +OH CH OH CH, OH CH, OH CH, OH C. (8 points) Identify the following relationships as enantiomeric, identical, or diastereomeric: A to B C to D A to C A to D d. (4 points) Identify the optically active molecules among A through D

Answer 1

maximum (0) Number of Stereol Somery a zn. na no. of Chiral Contre. Maximum No. of Streoisomers = 228 (6) Groven moklub: no Ichon 4 It has symmetry as numbering from either side of Chain b game -on schon Due to Symmetry, be identical, so Isomoss, only 4 some structures will out of 's' maximum is found. for example : will be similar to 25 RR 3R 3R че 4a or is in similar to similar to 35 2R as 35 "R YS As numbering can be done from either side.

Смои и - ОИ сч, он но ин но и и т ой моти и и смои tvon Since, A & B have only one opposite Configuration at *c, so they are diastereomers. I A,B : Diastreomer A toc Chon (и си - ОИ но- и о и - и ои — - ои - и - Choll И о Chron Morror : and Arc are mirror Image optically active. A & C - enantiomer

c toD Chon Clon -ой ton H on om Ио * H n on Chon con only С one y one Chrral Carbon has opposite Configurahon, so dia Stereomer IcID: Dias tromer A toD : A & D has opposite in two Choral Centre, so also dia Stero mer. Configuration those are (d) A sc are optically active B & D are optically inactive to Plane of symmetry, due