Synthesis of benzotriazole monomer

1. A method of preparing a monomer of formula (E):

where R 1 is H, a halogen atom, alkyl or alkoxy, R 4 is a group having a polymerizable C═C double bond and a linking moiety with an ester and/or ether group, and R 5 is H, or a straight or branched alkyl of 1-6 carbon atoms, the method comprising:

a) preparing a compound (F)

where R 2 is OR, and R is an organic leaving group;

b) deprotecting the R 2 group of the compound (F) to produce a compound (D):

where R 3 is OH; and then

c) reacting the compound (D) with an alkyl halide substituted with a polymerizable C═C double bond, or a carboxylic acid halide or anhydride having a polymerizable C═C double bond thereon to produce said compound (E).

2. A method as in claim 1 wherein R is an alkaryl group that is optionally substituted on the aromatic ring, a tetrahydropyranyl group that is optionally substituted on the pyrane ring or a t-butyldimethysilyl group.

3. A method as in claim 1 wherein in step c) the compound (D) is reacted with an alkyl halide substituted with a polymerizable C═C double bond.

4. A method as in claim 3 wherein the alkyl halide substituted with a polymerizable C═C double bond is a compound of the formula X—R 7 —R 8 where X is a labile halogen atom R 7 is alkylene and R 8 is a silyl group having a vinyl group attached to the silicon atom thereof.

5. A method as in claim 3 wherein the alkyl halide substituted with a polymerizable C═C double bond is an alkyl iodide having polymerizable C═C double bond.

6. A method as in claim 3 wherein the alkyl halide substituted with a polymerizable C═C double bond is a compound of the formula

I—R 7 Si(R 9 ) 2 CH═CH 2 , where R 7 is alkylene and the R 9 groups are the same or different monovalent hydrocarbon groups.