TargetIIT

Q1. Which of the following isomers of dichlorocyclohexane are optically active?
(a) 1,1 dichloro    
(b) 1,2 (cis) dichloro
(c) 1,2 (trans) dichloro
(d)  1,3 (cis) dichloro
(e) 1,3 (trans) dichloro
(f) 1,4 (cis) dichloro
(g) 1,4 (trans) dichloro

Q2. [image]41209401.jpg[/image]
Comment on the optical activity/inactivity of the following compound

2)

isn't above compound a meso compound it has a plane of symmetry.
optically inactive

Yeah it should be a meso compound but what if you reflect the compound about its bottom portion. then you cant superimpose the mirror image on the original compound. So it should be optically active.

yes. bhaiya if we reflect it about the plane of the carbon cycle.

(a) 1,1 dichloro                            inactive(since different grps shud be attached to carbon for it to be chiral)
(b) 1,2 (cis) dichloro                         inactive(symmetry)
(c) 1,2 (trans) dichloro                     active
(d)  1,3 (cis) dichloro                        inactive(symmetry)
(e) 1,3 (trans) dichloro                     active
(f) 1,4 (cis) dichloro                          inactive(symmetry)
(g) 1,4 (trans) dichloro                     inactive(point of symmetry)

(b) 1,2 (cis) is chiral but inactive
the compound has NO symmetry yet it is inactive.