Chapter 5, Problem 79CP

(a)

Interpretation Introduction

Interpretation:

A Newman projection of the allene when viewed from the left side of its $C=C=C$ unit has to be drawn.

Concept Introduction:

Allenes are compounds with two or more double bonds side-by side. Such bonds are called cumulated double bonds.

Allenes shows axial chirality. Axial chirality is a stereoisomerism resulting from the non-planar arrangemen6t of four groups in pairs about a chiral axis.

Newman projection: Newman projection of molecule is one type of representations for the alkanes, where the projection visualization from one carbon to another carbon. In this Newman projection, front carbon which represented as dot is called proximal and the back carbon which represented as circle is called distal.

    

From the angle of observer the front carbon is proximal and second carbon is distal.

In wedge-dash line representation, wedge is coming out of the plane and going behind the plane, the wedge and the dash of front carbon in Newman projection are pointing up and the wedge and the dash of back carbon in Newman projection are pointing down.

(b)

Interpretation Introduction

Interpretation:

Enantiomer of the given compound has to be drawn in bond-line format and as a Newman projection.

Concept Introduction:

Allenes are compounds with two or more double bonds side-by side. Such bonds are called cumulated double bonds.

Allenes shows axial chirality. Axial chirality is a stereoisomerism resulting from the non-planar arrangemen6t of four groups in pairs about a chiral axis.

Newman projection: Newman projection of molecule is one type of representations for the alkanes, where the projection visualization from one carbon to another carbon. In this Newman projection, front carbon which represented as dot is called proximal and the back carbon which represented as circle is called distal.

    

From the angle of observer the front carbon is proximal and second carbon is distal.

In wedge-dash line representation wedge is coming out of the plane and going behind the plane, the wedge and the dash of front carbon in Newman projection are pointing up and the wedge and the dash of back carbon in Newman projection are pointing down.

Enantiomers: These are stereoisomers that are not superimposable mirror images of each other and the configurations at all stereo genic centers are exactly opposite.

(c)

Interpretation Introduction

Interpretation:

Two diastereomers of the given compound has to be drawn in bond-line format and as a Newman projection.

Concept Introduction:

Allenes are compounds with two or more double bonds side-by side. Such bonds are called cumulated double bonds.

Allenes shows axial chirality. Axial chirality is a stereoisomerism resulting from the non-planar arrangemen6t of four groups in pairs about a chiral axis.

Newman projection: Newman projection of molecule is one type of representations for the alkanes, where the projection visualization from one carbon to another carbon. In this Newman projection, front carbon which represented as dot is called proximal and the back carbon which represented as circle is called distal.

    

From the angle of observer the front carbon is proximal and second carbon is distal.

In wedge-dash line representation wedge is coming out of the plane and going behind the plane, the wedge and the dash of front carbon in Newman projection are pointing up and the wedge and the dash of back carbon in Newman projection are pointing down.

Enantiomers: These are stereoisomers that are not superimposable mirror images of each other and the configurations at all stereo genic centers are exactly opposite.

Diastereomers: These are stereoisomers that are not enantiomers of one another. They have different physical properties so that they are viewed as different chemical substances.