REGIOSELECTIVE CYANATION OF PYRIDINE 1-OXIDES WITH TRIMETHYLSILANECARBONITRILE - A MODIFIED REISSERT-HENZE REACTION
REGIOSELECTIVE CYANATION OF PYRIDINE 1-OXIDES WITH TRIMETHYLSILANECARBONITRILE - A MODIFIED REISSERT-HENZE REACTION
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DOI：
10.1021/jo00156a053
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发表时间：
1983-01-01
影响因子：
3.6
通讯作者：
FIFE, WK
中科院分区：
文献类型：
--
作者：
FIFE, WK
方法A. b除非另有说明，产率基于分离的/再结晶产物和再结晶滤液的vpc分析（Carbowax 20 M, 5%，在Chromosorb W上）。括号内给出的产量是由：Feely， W. E.；海狸，e.m.j.。化学。社会科学学报，1999,8(1):404 - 407。c所有产物的熔点和/或红外和核磁共振光谱与文献数据非常吻合。d原油收率基于VPC分析（Carbowax 20 M 5%, on Chromosorb W）。e基于VPC分析（25 M熔融石英毛细管柱，OV-1涂层）的再结晶滤液收率。几种酰基氯化物作为反应催化剂的比较（表二）表明，二甲基氨甲酰氯在引起氰化反应方面特别有效。苯甲酰氯和三甲基硅烷腈分别过量2倍和5倍，也会影响2位吡啶-氧化物的定量氰化。由于副反应会形成酰基氰化物和酸酐，在苯甲酰氯和其他几种酰基氯化物存在的情况下，氰化反应需要过量的试剂。在通常的或改进的Reissert条件下得到1-氧化吡啶氰化的反复努力，最多只能得到4%的2-吡啶碳腈。三甲基硅烷腈作为氰化剂的特殊有效性可能是由于两个因素：它在有机溶剂中的溶解性和它与酰基卤化物反应生成酰基氰化物和随后的相关化合物的相对缓慢。
0 Method A. b Yields are based on isolated,/recrystallized products andVPC analysis (Carbowax 20 M, 5%, on Chromosorb W) of filtrates from recrystallizations, unless otherwise noted. Yields given in parentheses are values reported by: Feely, W. E.; Beavers, E. M. J. Am. Chem. Soc. 1959, 81, 4004-4007. c All products gave melting points and/or IR and NMR spectra that were in excellent agreement with literature data. d Yield based on VPC analysis (Carbowax 20 M 5%, on Chromosorb W) of crude product. e Yield based on VPC analysis (25 M fused silica capillary column with OV-1 coating) of filtrate from recrystallization.Comparison of several acyl chlorides as catalysts for the reaction (Table II) indicates the particular effectiveness of dimethylcarbamyl chloride in bringing about cyanation. Benzoyl chloride and trimethylsilanecarbonitrile in 2-and 5-fold excess, respectively, also effect quantitative cyana-tion of pyridine 1-oxide at the 2-position. An excess of reagents is required for cyanation in the presence of ben-zoyl chloride and perhaps several other acyl chlorides due to side reactions that form acyl cyanides5 and acid anhy-drides. 6 Repeated efforts to obtain cyanation of pyridine 1-oxide under the usual or modified Reissert conditions gave only 4% 2-pyridinecarbonitrile atbest. The particular effectiveness of trimethylsilanecarbonitrile as a cya-nating agent is probably due to two factors: its solubility in organic solvents and itsrelatively slow reaction with acyl halides to produce acyl cyanides and subsequent related compounds.