Sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 nanocrystallites as a magnetically separable catalyst for one-pot reductive amination of carbonyl compounds
A novel, environmentally friendly procedure has been developed for the preparation of secondary or tertiary amines by one-pot reductive amination of carbonyl compounds using sodium borohydride in the presence of a magnetically recoverable sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 [γ-Fe2O3@HAP-SO3H] at room temperature. The catalyst was easily separated from the reaction mixture by applying an external magnet and reused for six cycles without significant loss of catalytic activity.
A simpleone-potprocedure for the direct reductive amination of aldehydes using lithium powder and a catalytic amount of 4,4′-di-tert-butylbiphenyl (DTBB) or a polymer supported naphthalene as reducing system is described. The direct reductive amination of a variety of aldehydes with primary amines was achieved simply by adding a mixture of the corresponding carbonyl compound and the amine, over a
Asymmetric aza-Diels-Alder reaction: enantio- and diastereoselective reaction of imine mediated by Chiral Lewis acid
作者:Kouji Hattori、Hisashi Yamamoto
DOI:10.1016/s0040-4020(01)80532-9
日期:1993.2
asymmetric aza-Diels-Alder reaction usingchiral boron mediator is developed. The key to its success is the use of the chiral boron complex prepared in situ from (R)- or (S)- binaphthol and B(OPh)3. The enantiomeric reaction of prochiral imine affords products of up to 90% ee. The double asymmetric induction of chiral imine using α-benzylamine as a chiralauxiliary is achieved with almost complete diastereoselectivity
Asymmetric Petasis Borono‐Mannich Allylation Reactions Catalyzed by Chiral Biphenols
作者:Yao Jiang、Scott E. Schaus
DOI:10.1002/anie.201611332
日期:2017.2
Chiral biphenols catalyze the asymmetric Petasis borono‐Mannich allylation of aldehydes and amines through the use of a bench‐stable allyldioxaborolane. The reaction proceeds via a two‐step, one‐pot process and requires 2–8 mole % of 3,3′‐Ph2‐BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99 %) and high enantioselectivies
Direct and indirect reductive amination of aldehydes and ketones with solid acid-activated sodium borohydride under solvent-free conditions
作者:Byung Tae Cho、Sang Kyu Kang
DOI:10.1016/j.tet.2005.04.039
日期:2005.6
A simple and convenient procedure for reductive amination of aldehydes and ketonesusingsodiumborohydride activated by boric acid, p-toluenesulfonic acid monohydrate or benzoic acid as reducing agent under solvent-free conditions is described.