groups, one amide group and one oxygen atom from THF to form a distorted tetrahedron. Complexes I–III and a known complex (CH3C5H4)2YbNiPr2(THF) IV all can serve as the catalysts for addition of amines to nitriles to monosubstituted N-arylamidines. The activity depended on the central metals and amide groups, and the active sequence follows the trend IV ≈ III < I < II.
(CH 3 C 5 H 4)2 LnCl(THF)与NaNHAr在THF中的摩尔比为1:1的反应得到酰胺配合物(CH 3 C 5 H 4)2 LnNHAr(THF)[(Ar = 2,6 -Me 2 C 6 H 3, Ln = Yb(I),Y(III); Ar = 2,6- i Pr 2 C 6 H 3,Ln = Yb(II)]。复杂的I – III是同构的。每个络合物中的中心金属与THF的两个甲基环戊二烯基,一个酰胺基和一个氧原子配位,形成扭曲的四面体。配合物I – III和已知的配合物(CH 3 C 5 H 4)2 YbN i Pr 2(THF)IV都可以用作将胺加成腈到单取代N-芳基idine啶上的催化剂。依赖于中心金属和酰胺基团和活性序列的活性如下趋势IV ≈ III < 我 < II。
Synthesis, characterization of bridged bis(amidinate) lanthanide amides and their application as catalysts for addition of amines to nitriles for monosubstituted N-arylamidines
showed a good scope of aromatic amines. Some key reaction intermediates were isolated and structurally characterized, including the amidinate complexes LLn[NPhCNAr1](PhCN) (Ln = Y (8), Ln = Yb (9)), LYb[NAr2CNAr1](Ar2CN) (10), and amide complex 5 prepared by protonation of 9 by Ar1NH2. Reactivity studies of these complexes suggest that the present catalytic formation of monosubstituted N-arylamidines
桥联双(酰胺基)配体L,LLnNHAr 1(DME)(L = [Me 3 SiNC(Ph)N(CH 2)3 NC(Ph)NSiMe 3 ],Ar 1 = 2, 6- i Pr 2 C 6 H 3,DME =二甲氧基乙烷,Ln为Y(1),PR(2),钕(3),钆(4),镱(5)),镱(μ 2 -NHPh)] 2(μ 2 -L)2(6)和[LYB] 2(μ 2 -NHAr 2)2(7)(AR 2 =(ø -OMe)C 6 H ^ 4),由LLnCl(THF)的反应,合成2用相应的酰胺酰胺以高收率得到产物,并通过X射线晶体结构分析对其结构进行表征。发现所有络合物都是用于将芳族胺催化加成到芳族腈中以得到单取代的N-芳基idine啶的预催化剂。镧系金属和酰胺基的催化活性受镧系金属和-NHAr 2 <的活性序列Y(1)
Addition of Amines to Nitriles Catalyzed by Ytterbium Amides: An Efficient One-Step Synthesis of Monosubstituted <i>N</i>-Arylamidines
作者:Junfeng Wang、Fan Xu、Tao Cai、Qi Shen
DOI:10.1021/ol702739c
日期:2008.2.1
A one-step synthesis of monosubstituted N-arylamidinates via addition of amines to nitriles catalyzed by ytterbium amides is reported. The reactions with various substrates give the products in good to excellent yields with 5 mol % ytterbium at 100 degrees C under solvent-free conditions.
Calcium mediated efficient synthesis of <i>N</i>-arylamidines from organic nitriles and amines
作者:Indrani Banerjee、Shweta Sagar、Tarun K. Panda
DOI:10.1039/d0ob00805b
日期:——
electron-withdrawing to electron-donating substitutions as well as heterocyclic substitution. The reaction was carried out in a solvent-free medium under ambient conditions. The nucleophilic addition of aromatic amines to aryl nitriles led to good to excellent yields of the corresponding amidines. The reactivity of the amidines was further examined and the respective urea derivatives were achieved in excellent yields