Pyrrolyl potassium, reaction with

Although the hydroxy group is a relatively poor leaving group, its base-catalyzed nucleophilic substitution by the mechanism shown in Scheme 69 accounts not only for the hydrogenolysis of the 3-hydroxymethylindoles, but also for their SN reactions with ethoxide ions, cyanide ions and with piperidine. Nucleophilic substitution on 2-hydroxymethyl-pyrroles is generally precluded by the faster formation of the bis(2-pyrrolyl)methanes, but the synthesis of 2-cyano-2-(2,5-dimethyl-3-pyrroIyl) propanes from 2,5-dimethylpyrrole, propanone and potassium cyanide probably results from an SN reaction of the cyanide ion upon the initially formed 3-pyrrolylcarbinol (81USP4248784). The formation of (294)... 

In the reaction of EMME and the potassium salt of pyrrole in tetrahydro-furan (THF) at 0°C for 30 min, an addition product, ethoxy(l-pyrrolyl)-methylmalonate (115), could be isolated in 85% yield (82CB714). This ester (115) was hydrolyzed with potassium hydroxide in aqueous ethanol at reflux temperature to yield 95% dipotassium ethoxy( 1 -pyrrolyI)methylene-malonate (116), from which 1-pyrrolylmethylenemalonic acid (118) was... 

---