نتایج جستجو برای: mannich type reaction

تعداد نتایج: 1700335  

Journal: :Organic & biomolecular chemistry 2012
Yasuhiro Yamashita Hirotsugu Suzuki Shū Kobayashi

A catalytic Mannich reaction of a simple ester with no activating functionality at the α-position via a product-base mechanism was reported. The desired Mannich adducts were obtained in high yields using a catalytic amount of KH. This is a rare example of a Brønsted base-catalyzed Mannich reaction of unactivated esters as substrates.

2012
Yang Xue Ling-Po Li Yan-Hong He Zhi Guan

We reported the first enzyme-catalysed, direct, three-component asymmetric Mannich reaction using protease type XIV from Streptomyces griseus (SGP) in acetonitrile. Yields of up to 92% with enantioselectivities of up to 88% e.e. and diastereoselectivities of up to 92:8 (syn:anti) were achieved under the optimised conditions. This enzyme's catalytic promiscuity expands the application of this bi...

Journal: :Dalton transactions 2011
Charles D Swor Kyle R Hanson Lev N Zakharov David R Tyler

Non-coordinated hydroxymethylphosphines react readily with primary and secondary amines by the phosphorus Mannich reaction. To determine if this reactivity can be used to synthesize phosphine macrocycles, trans-Fe(DHMPE)(2)Cl(2) (DHMPE = 1,2-bis(dihydroxymethylphosphino)ethane) was prepared and reacted with various amines. However, no phosphorus Mannich reactivity was observed. In order to unde...

2017
Petr Funk Kamil Motyka Miroslav Soural Michal Malon Hiroyuki Koshino Joachim Kusz Jan Hlavac

2-Aminoquinolin-4(1H)-one was reacted with various primary/secondary amines and paraformaldehyde under Mannich reaction conditions. In the case of secondary amines, the reaction in N,N-dimethylformamide yielded expected Mannich products accompanied with 3,3'-methylenebis(2-aminoquinolin-4(1H)-one). Except these main products, the pyrimido[4,5-b]quinolin-5-one derivative was also identified as c...

Journal: :Organic & biomolecular chemistry 2014
Gert Callebaut Filip Colpaert Melinda Nonn Loránd Kiss Reijo Sillanpää Karl W Törnroos Ferenc Fülöp Norbert De Kimpe Sven Mangelinckx

Mannich-type reactions of O-Boc glycolic esters across chiral N-sulfinyl-α-chloroaldimines resulted in the efficient and syn-stereoselective synthesis of new γ-chloro-α-hydroxy-β-amino esters (dr > 99 : 1). The α-coordinating ability of the chlorine atom was of great importance for the diastereoselectivity of the Mannich-type reaction and overruled the chelation of the sulfinyl oxygen with the ...

2013
Yashumati R. Bhardwaj Monika Chauhan Ashutosh Pareek Dharma Kishore

Present work describes the synthesis of coumarin Mannich bases 4-7 by the application of Mannich reaction on 7-hydroxy-4-methyl coumarin 3 using conventional as well as microwave technology to compare the feasibility, reaction time and yield of the product. For this, 7-hydroxy-4-methyl coumarin 3 was prepared using Pechmann condensation reaction and Mannich bases (4-7) were synthesized by the r...

Journal: :RSC Advances 2023

The excellent catalytic activity of newly magnetic nanocatalyst FeAl 2 O 4 @PTMS-sulfaguanidine-SA in a one pot multicomponent Mannich-type reaction was used to obtain 2-piperazinyl quinoxaline derivatives with highly selective anti-proliferation efficacy.

Journal: :Organic & biomolecular chemistry 2012
Gert Callebaut Sven Mangelinckx Loránd Kiss Reijo Sillanpää Ferenc Fülöp Norbert De Kimpe

The efficient asymmetric synthesis of new chiral γ-chloro-α,β-diamino acid derivatives via highly diastereoselective Mannich-type reactions of N-(diphenylmethylene) glycine esters across a chiral α-chloro-N-p-toluenesulfinylimine was developed. The influence of the base, LDA or LiHMDS, used for the formation of the glycine enolates, was of great importance for the anti-/syn-diastereoselectivity...

Journal: :Chemical communications 2010
Daisuke Uraguchi Kyohei Koshimoto Takashi Ooi

A C(1)-symmetric chiral ammonium betaine has been developed, and its intramolecular ion-pairing structure in solid state and its catalytic performance to achieve the highly stereoselective Mannich-type reaction of 2-alkoxythiazol-5(4H)-ones are revealed.

Journal: :Chemical Society reviews 2008
Jorge M M Verkade Lieke J C van Hemert Peter J L M Quaedflieg Floris P J T Rutjes

The asymmetric Mannich reaction ranks among the most potent enantioselective and diastereoselective C-C-bond forming reactions. In recent years, organocatalysed versions of asymmetric Mannich processes have been increasingly reported and used in a rapidly growing number of applications. This tutorial review provides an overview of the recent history of the asymmetric organocatalysed Mannich rea...

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