Question

1. (23 pts.) Label each stereocenter (chiral center) as Ror S. Label each molecule as chiral or achiral. CH ен-он H- CH3 . Он CH2OH Сн,он h) н он В ньон нон НО-Б-н ен,он но- н H-LOH CH OH

Answer 1

Answers:

а. 4Н 2 6 2 (3R,4S)-3,4-dimethylhexane Clockwise durection 4th prior group in in the back So it is R 2 4 3 H Clockwise direction But 4 prior group in in the front So it is not R, it is S LO

Here 2nd position is chiral because it contains four different groups i.e one Cl, 1st carbon is R and 3rd carbon is S R isomer is more prior thsn S isomer 5 4 4 (1R,2r,3S)-2-chloro-1,3- dimethylcyclopentane 2 3 anticlock wise But 4th group is in the front therefore not S it is R

4. It has no chiral center 5 Molecule is achiral 2,3,4-trimethylpentane LO

1 Here 3rd carbon is a chiral centre 3 5 (R)-2,3,4-trimethylpent-1-ene

f. е. 4 Н CH3 4 3 Н- ОН 6 H- 5 Н- -СHз 1 ОН (1R,2R)-2-isopropylcyclohexan-1-ol (2S,3S)-butane-2.3-diol 5 h 5 g. CH2ОН CH-ОН Н ОН 4 Н- ОН Но- H 1 НО -н Н OH но- -н CH2OH CH2OH 1 (2S,4S)-pentane-1,2,3,4,5- pentaol (2R,3r,4S)-pentane-1,2,3,4,5-pentaol