With Reaction at a Carboxy Group

Alkoxycarbonylalkyl organo telluriums are conveniently prepared from tellurolates and alkoxycarbonylalkyl halides. The esters can be saponified in refluxing aqueous ethanol containing potassium hydroxide or sodium hydroxide. 

7-Carboxyheptyl 9-Iodo-non-8-en-l-yl Tellurium In 10 w/ of ethanol are dissolved 268 mg (0.5 mmol) of 7-methoxycarbonylheptyl 9-iodo-non-8-en-l-yl tellurium and 2 ml (2 mmol) of 1M aqueous sodium hydroxide solution arc added. The mixture is heated under reflux in the dark under argon for 0.5 h and then 50 ml of water are added. The mixture is then extracted with two 50-m/ portions of diethyl ether and the extracts are discarded. The pH of the aqueous layer is adjusted to 1 with 1 M hydrochloric acid, the acidic solution is extracted with two 50-m/ portions of diethyl ether, the combined extracts are washed with water, the separated diethyl ether solution is dried with anhydrous sodium sulfate, and the solvent evaporated. The oily residue is triturated with petroleum ether and the resultant solid is recrystallized from petroleum ether yield 175 mg (67%) m.p. 52-54°. The product should be stored in a sealed vial under argon at less than 0°. Similarly prepared were  

4-carhoxy-l-butyl 9-(4 -iodophenyl)-l-nonyl tellurium 3-carboxy-1-propyl 13-bromotridec-l2-en-l-yl tellurium butyl lS-carboxypentadec-7-en-l-yl tellurium 9-carboxy-l-nonyl pentyl tellurium 2-(2 -carboxyphenyl)-ethen-l-yl methyl tellurium  

2-(Ethoxycarbonyl)-ethen-l-yl aryl telluriums were similarly hydrolyzed without affecting the tellurium atom or the carbon-carbon double bond The free acids were isolated as sharp-melting solids in yields ranging from 60 to 95%. Examples of compounds prepared in this manner are  

CO-CJt4, 3-H3CO-C6H4, 3.S-(H,C0)2C H3, 4-H3C-CO-C6H4, 3-F-CfiHi, t-naphthyl 

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