Polymerizable dendrimers. Synthesis of a symmetrically branched methacryl derivative bearing eight ester groups

The synthesis of chiral acryl and methacryl derivatives containing four ester groups, tetramethyl 5‐((meth)acryloylamino)isophthalamido‐di‐2 L ‐succinate ( 2a and 2b ), was done by condensation of 5‐( N ‐acryloylamino)isophthalic acid ( 1a ) or 5‐( N ‐methacrylamino)isophthalic acid ( 1b ) with L ‐aspartic acid dimethyl ester in a mole ratio of 1:2. In a similar way, a methacryl monomer bearing eight ester groups, octamethyl 5,5′‐[5‐(methacryloylamino)‐isophthalamido]bis(isophthalamido)tetra‐2 L ‐succinate ( 6b ), was obtained using the Z‐protected intermediate tetramethyl 5‐(benzyloxycarbonylamino)isophthalamido‐di‐2 L ‐succinate ( 4 ). The monomers were homopolymerized radically with AIBN as initiator, yielding optically active polymers and oligomers ( 2a ′, 2b ′ and 6b ′) with branched side groups and degree of polymerization P n between 2 and 23, depending on the architecture of the monomers.