Beilstein Tutorial: Reaction Searching for Protecting Groups
Find Reactions Searching where one group reacts & another doesn't
Purpose: demonstrate how to:
Example: find journal articles to reactions where an acetonide
protecting group is removed from a terminal 1,2 diol in the presence of a
primary hydroxyl group which has been protected with any silyl group (RCH2O-Si).
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Open Beilstein. From in-library computers, use the
Search Tools page, and choose Beilstein Commander [UM Library
Terminal Services].
- The Terminal Services version should open to the Structure Editor in Beilstein.
If the Structure Editor does not open, try the following steps:
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Look at the Options menu, Structure Editors, and be sure that MDL CrossFire Structure Editor is checked.
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If the Select Database section is blank, you will need to click the red crossed-arrows icon to start the search session.
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Once connected, be sure that the Beilstein database checkbox is checked, and that Gmelin is unchecked. Tip: Gmelin is mostly for inorganic substances; Beilstein for organic.
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Select the Structure Editor icon to begin drawing the structure.
- Use the Pencil Tool on the Toolbox area to begin drawing the structure.
- Use the Function Bar to select the type of atom, bond, or ring that you
will draw.
- Tip: if some of the Bars are missing, use the View menu
to turn them on.
- Draw each of the reactants as shown below. Tip: use the select tool, then
copy/paste the reactants to use as the basis for drawing the products.
- Tip: Beilstein assumes exact rather than substructure searching [Hydrogens
are assumed at all open valencies]. To allow substitution at specific atoms,
move the cursor over the particular atom and click to open the Atom Attribute
Dialog box.
.
- Set the Free Sites to Max using the pulldown list.
Your screen should look similar to the following:
Next, we need to tell the system which pieces are reactants and which are products.
- Use the Editmode menu and select Reaction.
- Use the Select tool on the left column to select the two groups present
in the reactant. We are grouping them together since they are both present
in the same molecule.
- Then click on the reactant button.
- Follow the same procedure to designate the two groups present in the Product.
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