A Convenient and Improved Procedure for the Cyanation of Enamines and 1,3-Dicarbonyl Compounds

First Synthesis of 5-Cyanosalicylates by Formal [3+3] Cyclocondensations of 1,3-Bis(silyloxy)-1,3-butadienes

“…3-Cyano-4-(trimethylsilyloxy)pent-3-en-2-one (5) was prepared by silylation of known 32 3-cyano-acetylacetone. The TiCl 4 -mediated [3+3] cyclocondensation of 5 with 3a,b,d,l-n afforded the 5-cyanosalicylates 6a-f in moderate yields (except for 6d) ( Table 4).…”

Acylated cyanatoarenes - reagents for convenient cyanations

“…2-Cyano-l,3-diketones 7 are prepared when the sodium salts of 1,3-diketones are treated with compounds 2 under ice cooling [23].…”

“…2-Cyanopyrrole 6 is obtained by reaction of pyrrole with 1 at -70 "C in the presence of A1C13 as catalyst [23]. (20 ml).…”

“…Recently, we described the improved cyanation of aromatics, enamines and 1,3-dicarbonyl compounds using cyanatoarenes which are activated by carbonyl groups. We have found that cyanatoanthraquinone 1 and acylsubstituted cyanatobenzenes 2a, 2b act as convenient and powerful reagents for the introduction of hitrile functions [23,24]. The reagent of choice is determined by factors such as workingup procedures.…”

“…The yields obtained are only moderate [5, 21, 221. Despite the usefulness of the reagents mentioned above there are several factors limiting their general application, for example toxical or irritating activities, difficult accessibility, thermal instability, or small yields in some cases [12, 141. Recently, we described the improved cyanation of aromatics, enamines and 1,3-dicarbonyl compounds using cyanatoarenes which are activated by carbonyl groups. We have found that cyanatoanthraquinone 1 and acylsubstituted cyanatobenzenes 2a, 2b act as convenient and powerful reagents for the introduction of hitrile functions [23,24]. The reagent of choice is determined by factors such as workingup procedures.…”