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Ring flipping of the compound in the following conformation leads to:
The compound in ‘R’ configuration is:
In option B and C one of the terminal carbons has the same group, so it is neglected and in A H has least priority. Rotation gives S configuration and since it is at wedge position so we reverse it and S -> R we get the configuration to be R and hence A is correct.
Draw the structure of (2R, 3S) – 2, 3 – dichloropentane:
The most stable confirmation of following compound is:
Structure of 1, 2-dimethylcyclohexane is show below. Which of the following is an enantiomer to the given conformer:
Which is the most stable conformation of 1-chloro-4-methylcyclohexane:
Which of the following is a structure representation is R-Lactic acid:
(R)-lactic acid is an optically active form of lactic acid having (R)-configuration. It has a role as an Escherichia coli metabolite and a human metabolite. It is a conjugate acid of a (R)-lactate. It is an enantiomer of a (S)-lactic acid.
The chiral carbon atom has all four different group attached to it.
∴ It has one asymmetric or chiral carbon atom.
There option b) is correct.
The favored conformation (gauche, anti) for the molecule 1, 2-dichloro ethane; and 1,2-ethanediol will be respectively:
Which of the following term best describes the pair of compound shown below:
The major product is formed in the following reaction is:
The configurations at the three chiral centres in the bicyclodecano l given below, are:
The S enantiomer of ibuprofen is responsible for its pain – relieving properties. Which one of the following structures shown in (S) – ibuprofen:
Giving the numbers according to their priority we get:
Since 1 -> 2 -> 3 -> 4 is in the anti clockwise direction, It has S configuration.
Hence D is correct.
The major product formed in the following reaction is:
Here, basic conditions are given so
Most acidic H+ ion is removed which is attached to the carbon atom at benzylic position.
Then to stabilize the carbanion, elimination reaction mechanism takes place.
Leading to the removal of leaving group -OTs, forming a double bond between the two carbon atoms.
Hence D is correct.
Draw the structure of (1 R, 2 S, 3 S)-1, 2-dibromo-3-ethyl cyclo hexane:
The absolute configurations of the chiral centers in X and Y are:
Stereoisomers which are not mirror image isomers are:
The configuration of the following position of (I) and (II) is:
Which is the correct structure of D-Glyceraldehyde:
All the options A, B and C are same
When A is rotated by 90 degrees two times i.e. 180 degrees in plane of your screen then compound C will be obtained
Now by switching A two times or ‘even’ switch compound B will be obtained and configuration remained same as the switch was even
Hence all are the same, so, D is correct.
Which of the following structure represents meso compounds:
Which of the following statements is true for the compound (R)-2-butanol:
Among the structures given below, the most stable conformation for the following compound is:
Correct Answer :- c
Which of the following term correctly describes the structural relationship between cis-1,3 dimethyl cyclopentane and trans-1,3-dimethyl cyclopentane:
The gauche conformation (θ = 60o) of n-butane possess:
The absolute configuration of the two stereogenic (Chiral) centers in the following molecule is:
If minimum priority group on horizontal line is
Clockwise direction ⇒S
Anticlockwise rotation ⇒R
The gauche interaction values for Me/Me, Me/Br and Br/Br are 3.3, 0.8 and 3.0 kJ/mol, respectively. Among the following, the most stable conformation of 2,3-dibromobutane is:
The most stable conformations of 1,2-difluoroethane and dl-2, 3-butanediol are:
The -F and -OH groups in gauche positions to each other help them get involved in dipole-dipole interactions and h-bond interactions respectively. Gauche position is optimum so as to provide proximity for the stabilising interaction but not too close as in eclipsed positions to give rise to steric strains.