Bismuth specific derivatives

Catalytic oxidation ia the presence of metals is claimed as both nonspecific and specific for the 6-hydoxyl depending on the metals used and the conditions employed for the oxidation. Nonspecific oxidation is achieved with silver or copper and oxygen (243), and noble metals with bismuth and oxygen (244). Specific oxidation is claimed with platinum at pH 6—10 ia water ia the presence of oxygen (245). Related patents to water-soluble carboxylated derivatives of starch are Hoechst s on the oxidation of ethoxylated starch and another on the oxidation of sucrose to a tricarboxyhc acid. AH the oxidations are specific to primary hydroxyls and are with a platinum catalyst at pH near neutraUty ia the presence of oxygen (246,247). Polysaccharides as raw materials ia the detergent iadustry have been reviewed (248). 

There is an extensive literature on the chemistry of As, Sb, and Bi in addition to recent editions of standard textbooks, there is a book edited by Norman, which includes a chapter devoted to the coordination chemistry of these elements, as well as the article by McAuliffe in Comprehensive Coordination Chemistry (CCC, 1987). The vast organic chemistry of these elements falls outside the scope of the present chapter. Sources providing recent coverage of the organic chemistry include chapters by Wardell, in Comprehensive Organometallic Chemistry I and II, a volume in the Patai series The Chemistry of Organic Arsenic, Antimony and Bismuth Compounds), and chapters in Norman s book. These texts also list many reviews on specific classes of organo-derivatives. 

Bandyopadhyay et al. [50] synthesized a series of novel N-substituted pyrrole derivatives. The autiiors sought a simple and solvent-free ultrasound-assisted reaction for tiie synthesis of N-substituted pyrroles (12) by reacting 2,5-dime-thoxytetrahydrofuran (10) with aromatic, aliphatic, polyaromatic, and heteropolyaromatic amines (11) using bismuth nitrate pentahydrate as catalyst (Scheme 4). It should be mentioned that the addition of the bismuth salt, which is environmentally benign and nontoxic, increased tiie reaction yield from 55% to 99% and reduced the reaction time from 5h to 5 min. 5-(lH-Pyrrol-l-yl)-l,10-phenantiiroline and l-(phenanthren-2-yl)-lH-pyrrole have demonstrated cytotoxic specificity against liver cancer cell lines in vitro when compared with normal cultured primary hepatocytes. 

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