Steps to be taken in a screening experiment

Any synthetic procedure consists of a series of events where the experimenter may intervene at the various steps to determine the detailed settings of the experimental variables  

Substrate and reagents must be introduced into the reactor the reaction must proceed for a certain period of time during the reaction time additional reagents may be introduced upon completion of the desired reaction, the product is isolated by some work-up procedure, which in turn consists of another series of events (extraction, washings, precipitation etc.) 

It is evident, that even a simple synthesis can be modified in a very large number of ways if all possible experimental factors are to be considered. To reduce this 

It should be remembered that every new problem is a unique problem in certain respects It is not identical to previously studied synthetic procedures. It has its own back-ground history, e.g. there may be previous observations made on the reaction. Often there are also at least some assumptions on the mechanistic level. 

It may be non-unique in that respect that it resembles other, well-known, reactions. In that case, certain features of the procedure may be analogous to known methods, and this may simplify the problem. 

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