Electron transfer reactions of cyano substituted pyridines and quinolines with thermally generated diphenyl ketyl are reported. When E1/2(‐) for the heterocycle is less negative than ‐2V, electron transfer occurs from the ketyl to the heterocyclic base. In some cases the products obtained from the thermal reaction are the same as those obtained from the photochemical reaction with benzophenone and alcohols. In other cases different products are formed. Two bases, 2‐pyridinecarbonitrile and 2,4‐pyridinedicarbonitrile, undergo regiospecific reactions in which the course of the reaction is determined by the acidity of the medium. A mechanism in which the heterocyclic nitrogen is involved in the substitution process at the 2 position is proposed.

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Compounds III and IV.-To a paste of 30 mg. of I in chloroform was added excess hydriodic acid (sp. gr. = 1.7). After refluxing for 1 hr., the dark red crystalline material had changed to a fine emerald green solution. The solution was cooled, diluted with water, and extracted with chloroform. The chloroform layer was washed with a saturated sodium thiosulfate solution and water, dried over anhydrous sodium sulfate, and concentrated to dryness; 25 mg. of the crude product was obtained. Recrystallization from chloroform afforded III as dark red needles, m.p. >300°. Further purification of III was carried out by acetylation with a mixture of acetic anhydride and pyridine. The acetate (IV) of I was recrystallized from benzene and dried at 160°for 20 hr. under high vacuum; m.p. 295-297°.Anal. Caled, for C46H3402o: C, 60.91; H, 3.77. Found: C, 61.00; H, 3.48. Erythroglaucin (V).-To a suspension of 10 mg. of finely powdered I in 50 ml. of saturated sodium carbonate solution was added 500 mg. of sodium dithionite (under nitrogen). The solution was warmed on a boiling water bath for 10 min. After removal of unchanged I by filtration, the filtrate was acidified with hydrochloric acid and the acidic solution was extracted with benzene.

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