IDENTICAL, CONSTITUTIONAL ISOMERS, ENANTIOMERS, DIASTEREOMERS, IDENTICAL and MESO, or DIFFERENT CHEMICAL COMPOUNDS and not isomeric.
Click on the compounds to view the correct answer and a short explanation.
Converting the molecule on the right to a Fischer projection, only one "exchange" is necessary to reproduce the structure on the left, making the two molecules enantiomers.
Using the molecule on the left as reference and working with the molecule on the right, two "exchanges" are necessary to reproduce the structure of the top carbon, and one "exchange" is necessary to reproduce the bottom carbon, making the two molecules diastereomers (identical on top and enantiomeric on the bottom).
Using the molecule on the left as reference and working with the molecule on the right, two "exchanges" are necessary to reproduce the structure, making the two molecules identical.
Converting the molecule on the right to a Fischer projection, three "exchanges" are necessary to reproduce the structure on the left, making the two molecules enantiomers.
Using the molecule on the left as reference and working with the molecule on the right, two "exchanges" are necessary to reproduce the structure of the top carbon, and two "exchanges" are necessary to reproduce the bottom carbon, making the two molecules identical (identical on top and on the bottom).
Using the molecule on the left as reference and working with the molecule on the right, two "exchanges" are necessary to reproduce the structure, making the two molecules identical.
Using the molecule on the left as reference and working with the molecule on the right, one "exchange" is necessary to reproduce the structure of the top carbon, and one "exchange" is necessary to reproduce the bottom carbon, making the two molecules enantiomers (enantiomeric on top and on the bottom). The molecule on the left, however, can be clearly seen to have an internal plane of symmetry, making this a meso compound. Since a meso compound is superimposible on its mirror image, the two molecules must be identical and meso.
Converting the molecule on the left to a Fischer projection, two "exchanges" are necessary to reproduce the structure on the right, making the two molecules identical.
The molecule on the right has the molecular formula C9H20 which is different from the molecule on the left (C8H18), making them different chemical compounds. (Don't get confused by the line drawings!).
Since the hydroxyl groups in the two compounds are connected to different carbons in the cycloalkene, they are different chemical compounds with the same number and types of atoms, but with a different bonding sequence (constitution) and are therefore constitutional isomers.
The two molecules differ in the stereochemistry of the alkene which is connected to the chiral center. The two molecules, nonetheless, have the same bonding sequence (constitution) differing only in the arrangement of those atoms in space, making them stereoisomers. Since they are not enantiomeric, they must be diastereomers , which are defined as stereoisomers which are not enantiomers.
The two molecules differ in the relationship between the bridgehead methyl and the alkene. Both molecules contain two stereogenic carbons, but neither molecule is chiral since they both possess an internal plane of symmetry, making them both meso compounds. The two molecules, nonetheless, have the same bonding sequence (constitution) differing only in the arrangement of those atoms in space, making them stereoisomers. Since they are not enantiomeric, they must be diastereomers , which are defined as stereoisomers which are not enantiomers.
A simple rotation of the molecule shown on the right generates the structure shown on the left, making the two molecules identical. The molecule contains two stereogenic carbons, but is not chiral since it possess an internal plane of symmetry, making it a meso compound.
A simple rotation of the molecule shown on the right generates the mirror image of the structure shown on the left, making the two molecules enantiomers. The molecule contains two stereogenic carbons, and is chiral since it does not possess an internal plane of symmetry.
The two molecules differ in the relationship between the methyl and the tert-butyl groups. Both molecules possess an internal plane of symmetry, making them both achiral. The two molecules, nonetheless, have the same bonding sequence (constitution) differing only in the arrangement of those atoms in space, making them stereoisomers (actually, cis-trans isomers). Since they are not enantiomeric, they must be diastereomers , which are defined as stereoisomers which are not enantiomers.
