Acetonide protection in presence of acid sensitive O-protective group is very critical. You have to be very careful during this reaction. Usually acetonide protection has been carried out in presence of catalytic amount of p-TSA in acetone. 
But when you have acid sensitive protective group such as TBDMS, TBDPS etc, donot use p-TSA more than 0.001 equivalent otherwise acid sensitive protective group does not stand any more. The best procedure is the use of 2,2'-dimethoxy propane with 0.001 equivalent p-TSA in anhydrous THF. In this procedure your acid labile protective group will be intact in excellent yield and this is the beauty of this procedure.
Reference: Organic Syntheses, Vol. 82, p. 75 (2005); Coll. Vol. 11, p.88 (2009).
Reference: Organic Syntheses, Vol. 82, p. 75 (2005); Coll. Vol. 11, p.88 (2009).
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