Linked Questions

7 votes
2 answers
3k views

How to identify the asymmetric carbon in [4-(1-bromoethylidene)cyclohexyl]acetaldehyde? [duplicate]

How to identify an asymmetric carbon in the molecule below? Is the carbon identified by the asterisk asymmetric or not? I would say no as it has no 4 different groups attached. Is this correct? I ...
coder56's user avatar
  • 81
0 votes
0 answers
129 views

Does this molecule show cis-trans isomerism? [duplicate]

I want to find if the above molecule shows cis-trans isomerism, per an assignment. I am assuming that such isomerism, if present, will be shown by the substituted chlorines. It seems clear to me that ...
Ray Bradbury's user avatar
23 votes
3 answers
16k views

Why are allenes chiral?

How is 1-bromo-3-chloropropa-1,2-diene ($\ce{BrHC=C=CHCl}$) chiral? It doesn't have any carbon that is connected to four different groups.
Rajath Radhakrishnan's user avatar
19 votes
3 answers
3k views

Can geometrical isomers be enantiomers?

I have just been pondering upon the question above. I have found this example and I am sure they are enantiomers, but do they also count as geometrical isomers?
Harsh Katara's user avatar
14 votes
1 answer
2k views

What are the criteria for a molecule to be chiral?

What are the criteria for a molecule to be chiral? (We frequently get questions of this type, so this is an attempt to construct a suitable general answer for duping.)
Zhe's user avatar
  • 17.5k
5 votes
2 answers
570 views

Geometrical isomerism in 1-(chloromethylidene)-3,5-dimethylcyclohexane

Will this compound exhibit geometrical isomerism? This question was asked in JEE (Mains) 2020, which is an entrance exam held in India annually. The official answer given for this question was "...
Haider's user avatar
  • 93
1 vote
1 answer
3k views

Are alkylidene cycloalkanes planar molecules?

Above is an Alkylidene Cycloalkane. Its structure closely resembles that of allenes. According to my knowledge, allenes are non-planar molecules due to the two $\pi$-bonds being formed on almost ...
Ajay Subramanian's user avatar
2 votes
0 answers
420 views

Geometric isomers of substituted methylidenecyclohexane?

My thoughts on the problem: I am sort compound of sure C and D will not show geometric isomerism because of the same groups (H and H) attached. In compound A and B, suppose I swap the positions of H ...
NeshDude's user avatar
3 votes
2 answers
86 views

Does 1-chloro-4-(chloromethylidene)cyclohexane show geometrical isomerism?

Would this compound show geometrical isomerism, or GI for short? There certainly wouldn't be any restricted rotation for any atoms in the ring, as for the chiral carbon having chlorine and hydrogen (...
Mr Gubbo's user avatar
0 votes
0 answers
71 views

Why does 1-ethylidene-2,3-dimethylcyclopropane exhibit cis-trans isomerism?

I think the carbons 2 and 3 have different configuration according to the CIP rules which makes the groups different: Am I correct? Is there any official criteria regarding these cases ?
Ali's user avatar
  • 185
0 votes
0 answers
46 views

Why the C4 in this 1,3,4,5-substituted Cyclohexanes has a R/S configuration?

(1S,3S,4S,5S)-3,5-dimethoxy-1-phenylcyclohexane-1,4-dithiol. ChemDraw21 shows the C4 is S configuration. However I think C4 has two same function groups(C3 and C5 are both S configuration; C2-1-6 and ...
HasturQ's user avatar
  • 49