154139-29-4Relevant academic research and scientific papers
Atom transfer radical cyclisations of activated and unactivated N-allylhaloacetamides and N-homoallylhaloacetamides using chiral and non-chiral copper complexes
Clark, Andrew J.,De Campo, Floryan,Deeth, Robert J.,Filik, Robert P.,Gatard, Sylvain,Hunt, Nicola A.,Lastecoueres, Dominique,Thomas, Gerard H.,Verlhac, Jean-Baptiste,Wongtap, Hathaichanuk
, p. 671 - 680 (2007/10/03)
Activated N-tosyl-2,2,2-trichloroacetamide 6a, N-benzyl-2,2,2-trichloroacetamide 6d, 2,2-dichloroacetamides 6b-c and 6e-f and 2-monohaloacetamides lla-g undergo efficient 5-exo atom transfer radical cyclisations at room temperature mediated by CuCl or CuBr in the presence of tris(N,N-dimethylaminoethylene)amine 3 (trien-Me6). The efficiency and stereoselectivity of these cyclisations was found to be greater than existing published atom transfer procedures based upon CuCl(bipyridine), RuCl2(PPh3)3 and CuCl(TMEDA)2. The product distribution for the cyclisation onto alkyne 11g was found to be solvent dependent. Attempts to make larger ring sizes by endo cyclisation of N-tosylacetamides 19a-c led to a competing 5-exo ipso aromatic substitution into the N-tosyl group followed by re-aromatisation and loss of SO2 to furnish an amidyl radical. Cyclisation of N-homoallylacetamides 25a-d proceeded smoothly to give δ-lactams with a range of catalysts based upon ligands 2 and 26. The stereoselectivity of cyclisation to give γ lactams could be somewhat influenced by using chiral enantiopure copper complexes 28-30 suggesting that the reactions may involve metal-complexed radicals.
Indirect Electroreductive Cyclisation of N-Allylic and N-Propargylbromo Amides and o-Bromoacryloylanilides using Nickel(II) Complexes as Electron-transfer Catalysts
Ozaki, Shigeko,Matsushita, Hidenori,Ohmori, Hidenobu
, p. 2339 - 2344 (2007/10/02)
Nickel(II) complex-catalysed indirect electroreduction of N-allylic and N-propargyl-α-bromo amides and o-bromoacryloylanilides gave the corresponding 5-membered lactams.The product distribution was affected by the ability of the solvent to donate hydrogen atom.The electroreduction of N-allyl-N-(bromoacetyl)toluene-p-sulfonamide 1a in DMF and acetonitrile yielded as main product the 4-methylpyrrolidinone 2a (41percent) and the 4-(bromomethyl)pyrrolidinone 3a (33percent), respectively.On addition of 2 mol equiv. of a hydrogen-atom donor (Ph2PH) to the reaction of bromo amide 1a in acetonitrile, compound 1a provided compound 2a (58percent) as the sole cylised product.
