Supported cobalt complex-catalysed conjugate addition of indoles, amines and thiols to α,β-unsaturated compounds
作者:Fatemeh Rajabi、Sepideh Razavi、Rafael Luque
DOI:10.1039/b926599f
日期:——
A highly active and reusable supported Co(II) complex on SBA-15 shows an excellent activity and selectivity to target products in aza- and thia-Michael conjugate additions of indoles, amines and thiols to α,β-unsaturated compounds undersolventless mild reactionconditions. The Co-catalyst was also highly reusable and comparably more active than related catalysts in the reaction.
12-Tungstophosphoric acid (H 3 PW 12 O 40 )has been found to be an efficient and recyclable catalyst in promotingroom temperature Michael additions of amines and aryl thiols to α,β-unsaturated estersand acrylonitrile in water to afford the corresponding saturatedamines in good to excellent yields.
Aza-Michael additions of various amines with conjugate alkenes bearing electron withdrawing group catalyzed by polystyrene-supported aluminum chloride (Ps-AlCl3) without the use of any solvents. The catalyst shows high catalytic activity for both aromatic amines and aliphatic amines. Chemoselective additions of the two types of amines with conjugate alkenes are achieved. Regioselectiveadditions of two
A functionalizedionicliquid, 3‐(N,N‐dimethyldodecylammonium) propanesulfonic acid hydrogen sulphate ([DDPA][HSO4]) has been used as catalyst for the aza‐Michael reactions of aromaticamines with α,β‐unsaturated compounds at room temperature to produce β‐amino compounds in good yields. The catalyst can be reused for several times without obvious loss of the catalytic activity.
and ultraviolet–visible (UV-vis) spectroscopic investigations. Nanocrystalline zeolite catalysts of the present study are reusable. They exhibit significantly higher catalytic activities in aminolysis and alcoholysis compared with the hitherto known catalysts. A range of β-amino alcohols/β-alkoxy alcohols with high regioselectivity were synthesized using zirconosilicates. Application of these materials