scholarly journals C-N Bond Formation by Consecutive Continuous-Flow Reductions towards A Medicinally Relevant Piperazine Derivative

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2040
Author(s):  
Zsolt Fülöp ◽  
Péter Bana ◽  
István Greiner ◽  
János Éles
Keyword(s):  
Antipsychotic Drug ◽  
Catalytic Hydrogenation ◽  
Continuous Flow ◽  
Reductive Amination ◽  
Reduction Method ◽  
Bond Formation ◽  
Aluminum Salt ◽  
Line Extraction ◽  
Piperazine Derivative ◽  
Step Procedure

A new, continuous-flow consecutive reduction method was developed for the C-N bond formation in the synthesis of the key intermediate of the antipsychotic drug cariprazine. The two-step procedure consists of a DIBAL-H mediated selective ester reduction conducted in a novel, miniature alternating diameter reactor, followed by reductive amination using catalytic hydrogenation on 5% Pt/C. The connection of the optimized modules was accomplished using an at-line extraction to prevent precipitation of the aluminum salt byproducts.

scholarly journals Continuous-Flow Processes for the Production of Floxacin Intermediates: Efficient C–C Bond Formation through a Rapid and Strong Activation of Carboxylic Acids

2020 ◽  
Vol 02 (03) ◽  
pp. e128-e132
Author(s):  
Shao-Zheng Guo ◽  
Zhi-Qun Yu ◽  
Wei-Ke Su
Keyword(s):  
Reaction Time ◽  
Continuous Flow ◽  
Flow System ◽  
Bond Formation ◽  
Product Yield ◽  
Raw Material ◽  
Material Consumption ◽  
Tank Reactor ◽  
Mild Conditions ◽  
Flow Processes

AbstractThe development of highly efficient C–C bond formation methods for the synthesis of ethyl 2-(2,4-dichloro-5-fluorobenzoyl)-3-(dimethylamino)acrylate 1 in continuous flow processes has been described, which is based on the concept of rapid and efficient activation of carboxylic acid. 2,4-Dichloro-5-fluorobenzoic acid is rapidly converted into highly reactive 2,4-dichloro-5-fluorobenzoyl chloride by treating with inexpensive and less-toxic solid bis(trichloromethyl)carbonate. And then it rapidly reacts with ethyl 3-(dimethylamino)acrylate to afford the desired 1. This process can be performed under mild conditions. Compared with the traditional tank reactor process, less raw material consumption, higher product yield, less reaction time, higher operation safety ensured by more the environmentally friendly procedure, and process continuity are achieved in the continuous-flow system.

scholarly journals A versatile, immobilized gold catalyst for the reductive amination of aldehydes in batch and flow

2018 ◽  
Vol 3 (5) ◽  
pp. 714-721 ◽  
Author(s):  
Adela I. Carrillo ◽  
Patricia Llanes ◽  
Miquel A. Pericàs
Keyword(s):  
Gold Nanoparticles ◽  
Mesoporous Silica ◽  
Continuous Flow ◽  
Reductive Amination ◽  
Gold Catalyst

A process for the reductive amination of aldehydes in continuous flow catalyzed by gold nanoparticles immobilized onto mesoporous silica has been developed.

Automated Micro Measurement of Glucose by Means of o-Toluidine

1969 ◽  
Vol 15 (12) ◽  
pp. 1162-1170 ◽  
Author(s):  
Robert E Wenk ◽  
Ronald J Creno ◽  
Valerie Loock ◽  
John Bernard Henry
Keyword(s):  
Cerebrospinal Fluid ◽  
Closed System ◽  
Continuous Flow ◽  
Reduction Method ◽  
Flow Analysis ◽  
Protein Precipitation ◽  
Ferricyanide Reduction ◽  
Continuous Flow Analysis

Abstract The method described is based on Dubowski’s o-toluidine procedure for the determination of glucose in plasma, serum, or cerebrospinal fluid. It utilizes the rapidity, precision, and closed system of continuous flow analysis of an unmodified AutoAnalyzer to substantially increase sensitivity and accuracy in the low range. The method is more specific than the ferricyanide reduction method. Protein precipitation or dialysis are unnecessary except for hemolyzed specimens and only 0.042 ml of sample are required. The method is inexpensive, easily performed, and compares favorably on a practical basis with enzymatic, reducing, and other aniline dye methods.

Exploratory synthetic investigations related to 12a-deoxypillaromycinone

2002 ◽  
Vol 80 (6) ◽  
pp. 728-738 ◽  
Author(s):  
Lan Wang ◽  
Sanath K Meegalla ◽  
Cheng-Lin Fang ◽  
Nicholas Taylor ◽  
Russell Rodrigo
Keyword(s):  
Double Bond ◽  
Catalytic Hydrogenation ◽  
Alder Reaction ◽  
Diels Alder ◽  
Diels Alder Reaction ◽  
Step Procedure ◽  
Key Steps

Furfural is converted to suitably substituted AB synthon 21 for 12a-deoxypillaromycinone in 10 steps by a sequence involving the following key steps: intramolecular Diels-Alder reaction of a furan, 5-endo-trig cleavage of the oxabicyclo adducts 18, and catalytic hydrogenation of the double bond of a tetrasubstituted enone to produce 19. Enones 21a and 21b obtained by dehydrogenation of 19a and 19b, respectively, are then annulated with ethyl 2-methoxy-6-methylbenzoate in a four-step procedure to generate tetracyclic products 25 in 14 steps from furfural.

Salt-mediated polyol synthesis of silver nanowires in a continuous-flow tubular reactor

RSC Advances ◽  
2015 ◽  
Vol 5 (38) ◽  
pp. 29872-29877 ◽  
Author(s):  
Kan-Sen Chou ◽  
Chung-Yen Hsu ◽  
Bo-Tau Liu
Keyword(s):  
Continuous Flow ◽  
Reduction Method ◽  
Flow Reactor ◽  
Silver Nanowires ◽  
Tubular Reactor ◽  
Polyol Synthesis ◽  
Continuous Flow Reactor

Silver nanowires were successfully synthesized by a polyol reduction method in a continuous-flow reactor with a yield of 2 g h−1.

One-pot synthesis of carbazoles via tandem C–C cross-coupling and reductive amination

2016 ◽  
Vol 14 (1) ◽  
pp. 122-130 ◽  
Author(s):  
Deuk-Young Goo ◽  
Sang Kook Woo
Keyword(s):  
Natural Products ◽  
Reductive Amination ◽  
Bond Formation ◽  
Cross Coupling ◽  
Synthetic Route ◽  
One Pot ◽  
Highly Efficient ◽  
One Pot Synthesis ◽  
Synthetic Utility

We have developed a highly efficient synthetic route to carbazoles that employs sequential C–C/C–N bond formation via Suzuki cross-coupling and Cadogan cyclization. The developed method is compatible with electron neutral, rich or deficient substrates. The synthetic utility of this method was demonstrated by the concise syntheses of four natural products.

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