50870-56-9Relevant articles and documents
Activity of amino-functionalised mesoporous solid bases in microwave-assisted condensation reactions
Pineda, Antonio,Balu, Alina Mariana,Campelo, Juan Manuel,Romero, Antonio Angel,Luque, Rafael
, p. 1 - 6 (2013)
Aminopropylated functionalised hexagonal mesoporous silicas (HMS) and SBA-15 materials with different amino-loadings (5-30 wt.% NH2)were synthesized, characterised and their catalytic activitieswere subsequently investigated in the microwave-assisted Knoevenagel condensation of cyclohexanone and ethyl cyanoacetate as well as in the Michael reaction between 2-cyclohexen-1-one and nitromethane. The effects of the quantity of the catalyst in the reaction as well as a variety of microwave parameters including the power, temperature and time of microwave irradiation were optimised. High activities and selectivities to the condensation product could be achieved at short times of microwave irradiation for both base-catalysed processes. The low loaded HMS-5%NH2 and higher loaded SBA-15-20%NH2 were found to give the best activities in the reactions. This observation seems to be related to the significant deterioration observed in textural properties of HMS materials at amino-loadings larger than 10%.
Chiral Vicinal Diamines Derived from Mefloquine
Boratyński, Przemys?aw J.,Kowalczyk, Rafa?,Kucharski, Dawid J.
, p. 10654 - 10664 (2021/08/20)
Novel 1,2-diamines based on the mefloquine scaffold prepared in enantiomerically pure forms resemble 9-amino-Cinchona alkaloids. Most effectively, 11-aminomefloquine with an erythro configuration was obtained by conversion of 11-alcohol into azide and hydrogenation. Alkylation of a secondary amine unit was needed to arrive at diastereomeric threo-11-aminomefloquine and to introduce diversity. Most of the substitution reactions of the hydroxyl group to azido group proceeded with net retention of the configuration and involved actual aziridine or plausible aziridinium ion intermediates. Enantiomerically pure products were obtained by the resolution of either the initial mefloquine or one of the final products. The evaluation of the efficacy of the obtained vicinal diamines in enantioselective transformations proved that erythro-11-aminomefloquine is an effective catalyst in the asymmetric Michael addition of nitromethane to cyclohexanone (up to 96.5:3.5 er) surpassing epi-aminoquinine in terms of selectivity.
A kind of T-leucine derivative of the chiral amine compound and its preparation method and application
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Paragraph 0086-0089, (2017/01/26)
The invention discloses a tertiary leucine derived chiral amine compound as well as a preparation method and application thereof. The chiral amine compound contains a tert-butyl group, a primary amine, a secondary amine or a tertiary amine functional group and has the structural formula as shown in the specification; and chiral amine and salts thereof are prepared through simple preparation steps by taking common tert-leucine as the raw material to form the chiral amine compound. The chiral amine and the salts thereof can be used for the asymmetrical Michael additive reaction between alpha, beta-unsaturated ketone and a nucleophilic reagent such as nitrocarbol, malonic ester, substituted oxazolone and the like and the asymmetrical cascade reaction between the alpha, beta-unsaturated ketone and fifth-position unsaturated rhodanine, between fifth-position unsaturated hydantoin and the alpha, beta-unsaturated ketone; and the tertiary leucine derived chiral amine compound has very high catalytic activity and stereoselectivity as well as the highest diastereoselectivity of 30/1 and the highest enantioselectivity of 99%, and is wide in oligomer range.
Arginine- or lysine-catalyzed Michael addition of nitromethane to α,β-unsaturated ketones in aqueous media
Park, Seongsoon
, p. 3671 - 3674 (2015/02/05)
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