DESIGNER MONOMERS TO TAILORED DENDRIMERS - Designing Dendrimers - page 81

CHCO 2 CMe 3 gave the
desired RO 2 CC(COR 0 )(CH 2 CH 2 CO 2 CMe 3 ) 2 possessing a unique ketonic moie-
ty [169]; whereas with dialkyl malonate, symmetric products were isolated; however,
with unsymmetrical malonates, access to 1

Treatment of benzyl acetoacetate with 2 equiv. of CH 2 ¼

1) C-branchedmonomers should
be possible. Other related monomers have also been reported: (MeO 2 C) 2 C(CH 2 C-

! (2 þ

CH)(CH 2 CH 2 COMe) 2 ,(MeO 2 C) 2 C(CH 2 C CH)(CH 2 CH 2 CN) 2 , (MeO 2 C) 2 C(CH 2 -

CH ¼ CH 2 )(CH 2 CH 2 COMe) 2 , and (MeO 2 C) 2 C(CH 2 CH ¼ CH 2 OH)(CH 2 CH 2 COMe) 2 .

3.11 1 ! (2 þ 1) ARYL-BRANCHED MONOMERS

1)-branching pattern in
which 3,5-dibromo-4-iodophenylacetic acid were prepared [170] from ethyl
4-aminophenylacetate via bromination (Br 2 /AcOH) to give ethyl 3,5-dibromo-
4-aminophenylacetate, then diazotization (NaNO 2 /HCl, KI) to afford ethyl 3,5-
dibromo-4-iodophenylacetate, which was selectively substituted by the use of the
Suzuki cross-coupling reaction [171].

A novel series of dendrons possessing a 1 ! (2 þ

4-Iodo-2,6-dibromonitrobenzene was transformed in three steps to 4-iodo-
2,6-dibromodiethyltriazenylbenzene, which was coupled [Pd(Ph 3 P) 2 Cl 2 /Et 3 N]