A general, practical palladium-catalyzed cyanation of (hetero)aryl chlorides and bromides.
A general, practical palladium-catalyzed cyanation of (hetero)aryl chlorides and bromides.
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DOI：
10.1002/anie.201304188
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发表时间：
2013-09-16
影响因子：
16.6
通讯作者：
Buchwald, Stephen L.
中科院分区：
文献类型：
--
作者：
Senecal, Todd D.;Shu, Wei;Buchwald, Stephen L.
芳香族腈作为合成中间体和最终靶标具有广泛的应用前景例如，抗肿瘤药物来曲唑、抗抑郁药物西酞普兰和抗艾滋病毒药物依曲维林都含有芳基腈部分。传统上，苯腈的合成是通过苯胺的重氮化，然后用超化学计量量的氰化铜(I)进行Sandmeyer反应另一种生成苯腈的常见方法是rosenmond - von Braun反应，该反应通常需要在高温下用碘化芳基加热超计量量的氰化铜(I)最近的进展已经允许使用催化量的铜；然而，这些方法仍然有局限性。钯催化氰化物与芳基（伪）卤化物的偶联反应在较温和的条件下进行，并表现出较强的官能团耐受性。40年前，Takagi等人首次报道了钯催化氰化反应的方法尽管取得了很大的进步，[1,6]形成芳基腈的交叉偶联过程因其高度不可复制而闻名Grushin及其同事的机理研究表明，这部分是由于氰化物使催化剂失活，氰化物能够毒害催化循环中的所有中间体避免催化剂中毒的常用方法包括添加还原剂[9]或利用NaCN、KCN和Zn (CN) 2在有机溶剂中的低溶解度。Ushkov和Grushin的NaCN方法虽然具有很高的工业相关性，但需要使用严格的无水条件（手套箱设置），这使得许多合成化学家不方便或无法使用这种化学方法。此外，MCN盐（M= Na或K）通常在使用前研磨，以保证其应用中的溶解度和再现性。考虑到高毒性以及雾化细氰化物盐的可能性，研磨是有问题的。氰化锌在钯催化的官能化氰化反应中应用最为广泛
Aromatic nitriles have application in a variety of fields as both synthetic intermediates and final targets.[1] For example, the antineoplastic Letrozole, antidepressant Citalopram, and anti-HIV drug Etravirine all possess an aryl nitrile moiety. Traditionally, benzonitriles are synthesized by diazotization of anilines followed by a Sandmeyer reaction with superstoichiometric amounts of copper (I) cyanide.[2] Another common route to benzonitriles is the Rosenmund–von Braun reaction, which typically entails heating superstoichiometric amounts of copper (I) cyanide with an aryl iodide at elevated temperature.[3] Recent advances have allowed for the use of catalytic quantities of copper; however, these approaches still have limitations.[4]The palladium-catalyzed coupling of cyanide with aryl (pseudo) halides proceeds under milder conditions and displays increased functional-group tolerance. The first Pdcatalyzed cyanation method was reported by Takagi et al. 40 years ago.[5] Despite great advances,[1, 6] cross-coupling procedures to form aryl nitriles have obtained a reputation as being highly irreproducible.[7] Mechanistic studies by Grushin and co-workers have shown this is due, in part, to catalyst deactivation by cyanide, which is able to poison all of the intermediates in the catalytic cycle.[8] Common methods to avoid catalyst poisoning include the addition of reducing agents [9] or exploiting the low solubility of NaCN, KCN, and Zn (CN) 2 in organic solvents. The NaCN method by Ushkov and Grushin,[7] while of high industrial relevance, requires the use of rigorously anhydrous conditions (glovebox setup), which renders this chemistry inconvenient or inaccessible to many synthetic chemists. Furthermore, MCN salts (M= Na or K) are often milled prior to their use to guarantee solubility and reproducibility in their application. Milling is problematic considering the high toxicity in conjunction with the possibility of aerosolizing fine cyanide salts. Zinc cyanide finds the widest use in Pd-catalyzed cyanations of functionalized
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影响因子：
2
作者：
Cottyn, Betty;Vichard, Dominique;Raman, C. S.
通讯作者：
Raman, C. S.
影响因子：
3.9
作者：
Hajipour, Abdol R.;Karami, Kazem;Pirisedigh, Azadeh
通讯作者：
Pirisedigh, Azadeh
影响因子：
2.3
作者：
Hajipour, Abdol R.;Karami, Kazem;Pirisedigh, Azade
通讯作者：
Pirisedigh, Azade
影响因子：
15
作者：
Amatore, C;Broeker, G;Khalil, F
通讯作者：
Khalil, F
影响因子：
--
作者：
Rosenmund, KW;Struck, E
通讯作者：
Struck, E