Synthesis Without Protecting Croups

In order to overcome this internal incompatibility, one tends to protect the amino function in 7 as an amide, whereupon the reaction sequence can be carried out requiring at the end a final deprotection of the amine to reach the target 9. 

The most common cause of the use of protecting groups is the necessity to differentiate between two (or more) similar functional groups. Let it be alcohol groups in a polyol. For instance, a differentiation between the primary and secondary 

Handbook of Green Chemistry Volume 7 Green Synthesis, First Edition. Edited by Chao-Jun Li. 

It is easy to project that differentiation of a higher number of hydroxyl groups (functional groups) in a polyol such as one faces in carbohydrate chemistry may 

The BOM group likewise is orthogonal to the TBS group and serves to differentiate that particular hydroxyl group to be unveiled at later stage of the synthesis. 

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