Synthesis of polyfunctional secondary amines by the addition of functionalized zinc reagents to nitrosoarenes

Abstract

Addition of functionalized aryl, heteroaryl or adamantyl zinc reagents to various nitroso-arenes in the presence of magnesium salts and LiCl in THF produces after a reductive work-up with FeCl2 and NaBH4 in ethanol the corresponding polyfunctional secondary amines in high yields.

Room-Temperature CuI-Catalyzed Amination of Aryl Iodides and Aryl Bromides

“…N-benzylaniline (4g) 19. General procedure A (164 mg, 89%), eluting with petroleum ether/ethyl acetate (20:1), white solid; 1 H MHz, CDCl3) δ 7.42 -7.24 (m, 5H), 7.16 -7.12 (m, 1H), 6.63 (d, J = 5.0 Hz, 1H), 5.96 (s, 1H), 4.25 (s, 2H), 3.95 (s, 1H); 13 C NMR (100 MHz, CDCl3) δ 148.5, 139.3, 128.6, 127.7, 127.3, 125.2, 119.9, 96.1, 50.7.N-(4-methoxyphenyl)adamantan-1-amine (1h) 20. General NMR (100 MHz, CDCl3) δ 154.…”

Direct metal-free synthesis of diarylamines from 2-nitropropane via the twofold C–H functionalization of arenes

“…12 The nucle-ophilic attack by electron--rich arenes on 5 derived from primary nitroalkanes affords phosphorylated N--hydroxyhydr-oxylamine species 9, possessing a hydrogen atom at α-position, which undergoes facile elimination of H 3 PO 4 to furnish phosphorylated oxime 10. The reactivity of the latter is 4 to afford nitriles, which upon acid--mediated hydrolysis provide primary amines 11 or parent carboxylic acids (Scheme 2, route c). 13 Ketoximes 10 (R 1 = Alk) on the other hand underwent Beckman rearrangement with migration of the aryl group providing the corresponding anilides 12 (Scheme 2, route d).…”

“…By far the most powerful and abundantly used methodology is the transition metal--catalyzed C--N cross--coupling reaction between aniline derivatives and aryl halides developed by Buchwald and Hartwig (Scheme 1, path A). 2 The reaction of anilines 3 or aniline surrogates, such as nitrosoarenes, 4 nitroarenes, 5 or arylazides, 6 with stoichiometric arylmetal species have also been demonstrated (path B). A single example of catalytic arylation of anilines with arenes, involving activation of one aromatic C--H bond has recently been reported by Chang (path C).…”

Intermolecular Reductive C–N Cross Coupling of Nitroarenes and Boronic Acids by PIII/PV═O Catalysis

“…Hu has reported a related iron-catalyzed reductive C–N bond formation by reaction of nitroarenes with alkyl 6 and acyl 7 electrophiles. Stoichiometric main group metal approaches have also been described; Knochel, 8 Kürti, 9 and Niggemann 10 have demonstrated reductive conversion of nitroarenes to N -arylanilines.…”