1118917-00-2Relevant academic research and scientific papers
Metal-free access of bulky: N, N ′-diarylcarbodiimides and their reduction: Bulky N, N ′-diarylformamidines
Peddarao, Thota,Baishya, Ashim,Barman, Milan Kr.,Kumar, Ajay,Nembenna, Sharanappa
, p. 7627 - 7636 (2016/09/12)
A metal-free synthesis of symmetrical and unsymmetrical bulky N,N′-diaryl carbodiimides from the dehydrosulfurisation of their corresponding N,N′-diarylthiourea with 4-dimethylaminopyridine (DMAP) and iodine under mild reaction conditions with moderate to excellent yields has been established. In the literature, the classical method of dehydrosulfurisation of bulky N,N′-diarylthiourea to N,N′-diarylcarbodiimide has been reported using toxic metal oxide (HgO) and magnesium sulphate (MgSO4) under harsh reaction conditions. Furthermore, easy access to 1,3-disubstituted symmetric and unsymmetrical N,N′-diaryl formamidines involving the reaction of symmetrical and unsymmetrical N,N′-diaryl carbodiimides with sodium borohydride is described. The widely used method for the preparation of bulky N,N′-diaryl formamidines is the treatment of primary amines with triethylorthoformate in the presence of acid under high temperature reaction conditions.
A modular synthesis of highly substituted imidazolium salts
Hirano, Keiichi,Urban, Slawomir,Wang, Congyang,Glorius, Frank
supporting information; experimental part, p. 1019 - 1022 (2009/07/18)
A versatile and modular one-pot method for the preparation of differently substituted symmetrical and unsymmetrical imidazolium salts is reported, and 19 examples are given. In the key step, readily available formamidines and α-halo ketones are coupled to give imidazolinium salts 3, followed by imidazolium salt formation by acylation-induced elimination. For many substitution patterns of the imidazolium salt products, this efficient strategy compares favorably with well-known processes in terms of yield, ease of synthesis, and robustness.
