Reaction chromatography alkoxy groups

Initial work was carried out with 3,9-bis(methylene-2,4,8,10-tetraoxaspiro[5,5] undecane) where R = H (11). However, this monomer contains two electron donor alkoxy groups on one double bond which is thus highly susceptible to a cationic polymerization. For this reason, the monomer is extremely difficult to handle and cannot be analyzed by gas chromatography since it does not survive passage through the column. It is prepared by the dehydrohalogen-ation reaction of the reaction product of pentaerythritol and chloro-acetaldehyde,... 

A highly fluorous alkoxy ethyl ether was synthesized and used as a protective group of alcohols. Treatment of an ether solution of 1 equivalent of a primary alcohol and 3 equivalents of the fluorous vinyl ether 29 with 5 mol% of camphorsulfonic acid (CS A) for 3 h at room temperature provided the desired protected alcohols 30 in 84-93% yields (Scheme 33). The products and the excess fluorous vinyl ether were extracted with FC-72 and then separated by column chromatography. Secondary and even tertiary alcohols were similarly protected in good yields in THF at 65°C for 30 5 min. The protected fluorous acetals were treated in a 1 1 solution of ether and methanol with 5 mol% of CSA for 1 h for deprotection. After completion of the reaction, the products were isolated in pure form by simple three-phase extraction (reaction mixture/saturated aqueous NaHC03/FC-72). 

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