Some molecules have two or more stereogenic centers. David Rawn, in Organic Chemistry Study Guide, 2015 8.6 Molecules with Two or More Stereogenic Centers Indeed, it maybe more useful to begin the search with the racemic compound and use that information to guide any search with the enantiopure compound. The main lesson is that one should not limit the search to the structure with all “wedges” and “dashes” incorporated, but also search using the racemic structure (line notation but no wedges or dashes).
Searching exact structures with all sterochemistry intact (an enantiopure structure) may return no hits, whereas the same search for the racemic structure may return many hits or at least related structures that can help with the planning.
The second issue deals with search engines. Disconnection of a bond away from the stereogenic center usually leads to a less efficient and less desirable retrosynthesis, and often more difficult. First, disconnection should be done at a C C bond where one of the carbon atoms is a stereogenic center. Stereochemistry is an important issue in any synthesis.
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