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• Within the Program Manager, select the CS ChemDraw program-item icon.
• Or, within the File Manager, select the ChemDraw.exe file icon.

The CS ChemDraw Program Icon

From the File menu of the Program or File Manager, choose Open.

After a brief pause a ChemDraw document window appears. Once you have created ChemDraw documents there are several ways that you can open them. See Chapter 15, Working With Documents, for more information.

Drawing Basics

Drawing operations in CS ChemDraw are performed using a pointing device, usually a mouse.

To select something on the screen, move the mouse until the pointer is positioned over the object you want to select. Press and release the mouse button to indicate that you have made your selection; this is called a click. Sometimes, you will press the mouse button twice in rapid succession (double-click) to carry out a different function from clicking.

One way to draw an object is to position the pointer in a document window, press and hold down the mouse button, move the mouse along a surface, and then release the mouse button. This method is known as dragging.

In CS ChemDraw, the SHIFT, ALT and CTRL keys are used to modify functions performed by the mouse. The SHIFT key generally modifies how objects are selected. For example, SHIFT+drag means hold down the SHIFT key with one hand, while dragging the mouse with the other hand. The ALT key generally adds special effects to dragging objects, such as duplicating. For example, ALT+drag means to hold down the ALT key with one hand, while dragging the mouse with the other hand. The Control key is used to apply or remove drawing constraints, such as fixed length. For example, to CTRL+drag, hold down the Control key with one hand, while dragging the mouse.

Document Settings

Document settings are user definable settings that are applied to the current document. Document settings include Drawing Settings, Caption Text Settings, Label Text Settings, Print Setup, and in CS ChemDraw Pro, the Color Palette. Drawing Settings affects drawing related options such as the fixed length used to draw bonds. Text Settings affect text related options like the font used for atom labels and captions. In CS ChemDraw Pro, the Color Palette affects the colors available to colorize objects. The Print Setup affects options like the page size used.

As you become familiar with CS ChemDraw you can change these settings to fit your needs. You can also save different sets of document settings in style sheets to be used for special instances, such as journal articles, textbook chapters, slide presentations and so on.

To select a bond tool:

• Click a bond tool icon in the Tools window.

Fixed Lengths

To draw bonds that are constrained to a fixed length:

• From the Tools menu, choose Fixed Lengths.

A check mark appears next to the Fixed Lengths command indicating that it is turned on. When Fixed Lengths is turned on, all the bonds you draw are constrained to the fixed length specified in the Drawing Settings dialog box.

Select a bond tool.

• Drag from one end of the bond to the other.

The Message area at the bottom left of a document window shows the length and angle of the bond as you drag. The bond will not extend further than the fixed length.

Dative Bonds and Wedged Bonds

Dative bonds and wedged bonds are drawn with a specific orientation in a document window.

To draw a dative bond:

• Select the Dative Bond tool.
• Drag from the positive to the negative end of the dative bond.

To draw a wedged bond:

• Select one of the wedged bond tools.
• Drag from the narrow end of the wedged bond to the wide end of the wedged bond.

If the orientation of the dative bond is not what you want:

• Click the center of the dative or wedge bond using its tool.

The orientation of the bond is inverted.

Preferences Guide – Units

The units you use are chosen from the Units pop-up menu in the Preferences dialog box. You can choose centimeters, inches, or points.

To change the units:

• Choose Preferences from the File menu.
• Choose a new unit measurement from the Units pop-up menu, then click the OK button.

Adding Bonds to Chemical Structures

To add a bond to a pre-existing atom:

• Select a bond tool.
• Point to an atom.

A highlight box appears over the atom indicating where the bond will be joined (if you are pointing to a bond, the highlight box encompasses the entire bond).

A Highlight Box on an Atom

• Drag away from the atom to the end of the new bond.

A new bond is drawn and joined to the atom where the highlight box appeared. By using this dragging method for drawing the bond, you can control the orientation of the other end of the bond.

Preferences Guide – Tolerance

The size of highlight box is controlled by the measurement in the box labeled "Tolerance" in the Preferences dialog box. The default setting for the Tolerance is 5 pixels. This means, for instance, that the highlight box appears on atoms if the pointer is located in a square region +/- 5 pixels from the atom.

To change the Tolerance:

• Choose Preferences from the File menu.
• Click the up or down Tolerance control arrow to increase or decrease the tolerance.
• Click the OK button.

Adding a Bond by Clicking

To quickly add a bond:

• Select a bond tool.
• Click an atom.

A new bond is drawn and is joined to the atom you clicked. Bonds drawn by this method are always drawn using the Fixed Length specified in the Drawing Settings dialog box. The angle that the deposited bond makes with its nearest neighbor is equal to the Chain Angle set in the Drawing Settings dialog box. If this angle cannot be established, a smaller angle is used.

For example, to draw a molecule of 2,4-dimethylpentane:

• Make sure that a check mark appears next to the Fixed Lengths and Fixed Angles commands in the Tools menu.
• Draw a bond oriented at 30 degrees with respect to the positive X axis as shown below.
• Click the lower left atom to deposit a bond. Alternatively, you can drag the bond from one end to the other, making any angle between the bond and the positive X axis.
• Click the atoms at either end of this structure.

Drawing a Ring

To draw a ring:

• Select a Ring tool.
• Position the pointer in a document window.

When you point in a document window, the pointer changes to a ring tool pointer. The highlight box on the ring tool pointer indicates the atom that is drawn first. The bond directly below the highlight box is the bond that is drawn first.

First Atom and Bond Drawn as Indicated on Ring Tool Pointers

• Drag from the beginning to the end of the first bond.

If Fixed Lengths is on when you draw a ring, the length of each bond in the ring is automatically set to the fixed length. If Fixed Angles is on, the angle the first bond in the ring makes with the X axis is restricted to 15 degree increments. See "Drawing Bonds with Fixed Lengths and Fixed Angles" earlier in this chapter for more information.

Cylcohexane Chair Ring Tools

The Cyclohexane Chair Ring tools can be drawn in two orientations. Using the methods previously discussed, the chair is drawn in a horizontal orientation.

To change a Cyclohexane Chair Ring to a vertical orientation:

• Select one of the Cyclohexane Chair Ring tools.
• SHIFT+drag from the beginning of the first bond to the end of the bond or, SHIFT+click in a document window.

For example, the illustration below shows the affect the SHIFT key has on the orientation of the Cyclohexane Chair rings. The arrow indicates the first bond drawn and the direction it is drawn for the Cyclohexane Chair Ring tool (2).

Cyclopentadiene and Benzene Ring Tools

The double bonds in the Cyclopentadiene or Benzene ring tools can be drawn in either of two orientations.

Normally, the first bond drawn is a double bond. This is the orientation indicated on the Cyclopentadiene and Benzene Ring tool pointers. You can draw in this orientation by the methods previously discussed.

To shift the orientation so that the first bond drawn is a single bond:

• SHIFT+drag from the beginning of the first single bond to the end of the single bond.
• Or, SHIFT+click in a document window to deposit the bond with a Fixed Length.

The ring is drawn in an alternate orientation.