136167-42-5Relevant academic research and scientific papers
Ligand-Free Copper-Catalyzed Ullmann-Type C?O Bond Formation in Non-Innocent Deep Eutectic Solvents under Aerobic Conditions
Quivelli, Andrea Francesca,Marinò, Manuela,Vitale, Paola,García-álvarez, Joaquín,Perna, Filippo M.,Capriati, Vito
, (2021/12/09)
An efficient and novel protocol was developed for a Cu-catalyzed Ullmann-type aryl alkyl ether synthesis by reacting various (hetero)aryl halides (Cl, Br, I) with alcohols as active components of environmentally benign choline chloride-based eutectic mixtures. Under optimized conditions, the reaction proceeded under mild conditions (80 °C) in air, in the absence of additional ligands, with a catalyst [CuI or CuII species] loading up to 5 mol% and K2CO3 as the base, providing the desired aryloxy derivatives in up to 98 % yield. The potential application of the methodology was demonstrated in the valorization of cheap, easily available, and naturally occurring polyols (e. g., glycerol) for the synthesis of some pharmacologically active aryloxypropanediols (Guaiphenesin, Mephenesin, and Chlorphenesin) on a 2 g scale in 70–96 % yield. Catalyst, base, and deep eutectic solvent could easily and successfully be recycled up to seven times with an E-factor as low as 5.76.
Copper(ii)-catalyzed C-O coupling of aryl bromides with aliphatic diols: Synthesis of ethers, phenols, and benzo-fused cyclic ethers
Liu, Yajun,Park, Se Kyung,Xiao, Yan,Chae, Junghyun
supporting information, p. 4747 - 4753 (2014/06/24)
A highly efficient copper-catalyzed C-O cross-coupling reaction between aryl bromides and aliphatic diols has been developed employing a cheaper, more efficient, and easily removable copper(ii) catalyst. A broad range of aryl bromides were coupled with aliphatic diols of different lengths using 5 mol% CuCl2 and 3 equivalents of K2CO3 in the absence of any other ligands or solvents to afford the corresponding hydroxyalkyl aryl ethers in good to excellent yields. In this newly developed protocol, aliphatic diols have multilateral functions as coupling reactants, ligands, and solvents. The resulting hydroxyalkyl aryl ethers were further readily converted into the corresponding phenols, presenting a valuable alternative way to phenols from aryl bromides. Furthermore, it was demonstrated that they are useful intermediates for more advanced molecules such as benzofurans and benzo-fused cyclic ethers. This journal is
Discovery of a novel class of 2-mercaptohexanoic acid derivatives as highly active PPARα agonists
Zettl, Heiko,Steri, Ramona,Laemmerhofer, Michael,Schubert-Zsilavecz, Manfred
supporting information; experimental part, p. 4421 - 4426 (2010/04/05)
A novel and robust scaffold for highly active PPARα agonists based on the 2-mercaptohexanoic acid substructure is presented. Systematic structural variation of the substitution pattern of the phenolic backbone yielded detailed SAR especially of ortho and
Reactions of γ-arylalkanols via aryl radical cation and alkoxyl radical intermediates. Part 3. Reactions of 3-arylprop-1-yl hydroperoxides with iron(II) in the presence of copper(II)
Goosen, Andre,Marais, Charles F.,McCleland, Cedric W.,Rinaldi, Fabrizio C.
, p. 1227 - 1236 (2007/10/02)
A strategy for comparing the 1,5- and 1,6-cyclisation reactions of 3-phenylpropan-1-oxyl radicals is described.Iron(II)-catalysed reduction of 3-(p-methylphenyl)prop-1-yl hydroperoxide and its para-chloro and para-methoxy-substituted analogues, carried out in the presence of copper(II), has been found to give in each case the appropriate para-substituted 3-phenylpropan-1-ol, 3-phenylpropanal and a low yield of a mixture of isomeric 6- and 7-substituted chromans.The alcohols are proposed to form via reduction of either the hydroperoxide or the resulting alkoxyl radical or its cyclised intermediates, and the aldehydes as a result of rearrangement of the alkoxyl radical to an α-hydroxy alkyl radical which subsequently undergoes oxidation.The 7-substituted chromans, which arise directly from 1,6-cyclisation of the alkoxyl radical, were found to dominate the 6-substituted isomers which result from rearrangement of 1,5-cyclised intermediates.This effect is attributed to inefficient interception of the 1,5-cyclised radical intermediate which permits equilibration to the thermodynamically more stable 1,6-cyclised radical isomer to occur.The effect of pH on the reactions has been investigated and although no products typical of the intermediacy of aryl radical cations were detected (even under highly acidic conditions), the formation of such intermediates cannot be excluded.Semiempirical MO calculations have been carried out (at the PM3 level of approximation) on a series of model compounds, yielding results which have clarified our understanding of the effect of substituents on the stabilities of the various intermediates arising from the cyclisation reactions of 3-phenylpropan-1-oxyl radicals.Furthermore, these calculations have supported our assumptions regarding the probability and specificity of rearrangements of the spirodienyl intermediates.
The Gas-phase Smiles Rearrangement. The Effect of Ring Substitution. An 18O Labelling Study
Eichinger, Peter C. H.,Bowie, John H.
, p. 995 - 999 (2007/10/02)
The gas-phase Smiles reaction of RC6H4O(CH2)nO(1-) (n = 2 or 3) is an ipso rearrangement which is strongly influenced by the nature of the substituent R.Electron-withdrawing groups enhance the rearrangement.When the substituent R is halogen or Me, and occupies the ortho position, ortho cyclization competes with the Smiles rearrangement.
