Sb. Kahl et J. Li, SYNTHESIS AND CHARACTERIZATION OF A BORONATED METALLOPHTHALOCYANINE FOR BORON NEUTRON-CAPTURE THERAPY, Inorganic chemistry, 35(13), 1996, pp. 3878-3880
Synthesis of the first fully characterized, water-soluble boronated ph
thalocyanine is reported. Reaction of 4-nitrophthalonitrile with dimet
hyl malonate in the presence of base yielded dimethyl (3,4-dicyanophen
yl)malonate which was converted into dimethyl (3,4-dicyanophenyl)propa
rgylmalonate by sequential treatment with potassium hydroxide and prop
argyl bromide. Formation of the o-carborane cage was accomplished by r
eaction of the alkyne with decaborane in acetonitrile at reflux. High-
temperature solid state condensation of the resulting o-carboranylphth
alonitrile with cobalt(II) chloride followed by ester deprotection and
cation exchange provided the water-soluble closo-carbonylphthalocyani
ne product. The product contains 40 boron atoms (27% boron by weight)
and may be useful as a tumor-seeking boron delivery agent for boron ne
utron capture therapy of cancer.