A facile synthesis of 3,4-dialkyl-3,4-dihydro-2H-1,3-benzoxazin-2-ones and naphthoxazin-2-ones and their reactions with organolithium and Grignard reagents – Preparation of N-[1-(2′-hydroxyphenyl)alkyl]amides

2004 ◽  
Vol 82 (8) ◽  
pp. 1314-1321 ◽  
Author(s):  
Cristina Cimarelli ◽  
Gianni Palmieri ◽  
Emanuela Volpini
Keyword(s):  
Reaction Mechanism ◽  
Conformational Analysis ◽  
Grignard Reagents ◽  
Facile Synthesis ◽  
Simple Method ◽  
Relative Configuration ◽  
Organometallic Reagents ◽  
H Nmr ◽  
High Yields

A facile and simple method for the preparation of 3,4-dialkyl-3,4-dihydro-2H-1,3-benzoxazin-2-ones or naphthoxazin-2-ones in high yields from aminoalkylphenols and aminoalkylnaphthols is described. The reactions of the products obtained with organolithium and Grignard reagents were studied, and a method for the preparation of N-[1-(2-hydroxyphenyl)alkyl]-N-alkylamides, which are of pharmaceutical interest, from benzoxazinones was developed. A possible reaction mechanism is also proposed. The relative configuration of chiral products was determined from conformational analysis of 1H NMR spectra.Key words: benzoxazinones, naphthoxazinones, organometallic reagents, amide preparation, aminoalkylphenols.

scholarly journals Copper-catalyzed asymmetric allylic substitution reactions with organozinc and Grignard reagents

2008 ◽  
Vol 80 (5) ◽  
pp. 1025-1037 ◽  
Author(s):  
Koen Geurts ◽  
Stephen P. Fletcher ◽  
Anthoni W. van Zijl ◽  
Adriaan J. Minnaard ◽  
Ben L. Feringa
Keyword(s):  
Building Blocks ◽  
Field Work ◽  
Grignard Reagents ◽  
Allylic Alcohols ◽  
Substitution Reactions ◽  
Organometallic Reagents ◽  
Bond Forming ◽  
Allylic Alkylations ◽  
Ferrocenyl Ligands ◽  
High Yields

Asymmetric allylic alkylations (AAAs) are among the most powerful C-C bond-forming reactions. We present a brief overview of copper-catalyzed AAAs with organometallic reagents and discuss our own contributions to this field. Work with zinc reagents and phosphoramidite ligands provided a framework for later developments which employ Grignard reagents and ferrocenyl ligands. High yields and excellent regioselectivities and enantioselectivities are achieved. The AAAs may be more general than previously envisioned, in terms of using substrates functionalized with heteroatoms at various positions; heteroatom substituents at the γ-position provide densely functionalized building blocks. These h-AAA reactions rely on the design of appropriate substrates containing heteroatoms and have allowed us to demonstrate viable new approaches toward the synthesis of versatile organic building blocks. We illustrate that the chiral secondary allylic alcohols, primary homo-allylic alcohols and amines can readily be obtained in high enantiomeric purity in a catalytic asymmetric fashion by copper-catalyzed AAAs. Furthermore, we show that manipulation of the terminal olefin provides chiral building blocks where the ee of the starting materials is preserved.

A Simple Method for Preparing Fibrinogen

1966 ◽  
Vol 16 (01/02) ◽  
pp. 198-206 ◽  
Author(s):  
W Straughn ◽  
R. H Wagner
Keyword(s):  
Barium Sulfate ◽  
Caproic Acid ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Human Fibrinogen ◽  
Simple Method ◽  
High Yields ◽  
Marked Stability

SummaryA simple new procedure is reported for the isolation of canine, bovine, porcine, and human fibrinogen. Two molar β-alanine is used to precipitate fibrinogen from barium sulfate adsorbed plasma. The procedure is characterized by dependability and high yields. The material is 95% to 98% clottable protein but still contains impurities such as plasminogen and fibrin-stabilizing factor. Plasminogen may be removed by adsorption with charcoal. The fibrinogen preparations exhibit marked stability to freezing, lyophilization, and dialysis. Epsilon-amino-n-caproic acid and gamma-aminobutyric acid which were also studied have the property of precipitating proteins from plasma but lack the specificity for fibrinogen found with β-alanine.

Ultrasound-assisted aqua-mediated synthesis of multi-substituted tetrahydropyridine-3-carboxylates using N-carboxymethyl-3-pyridinium hydrogensulfate ([N-CH2CO2H-3-pic]+HSO4−) as a new efficient ionic liquid catalyst

2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Kobra Nikoofar ◽  
Fatemeh Shahriyari
Keyword(s):  
Ionic Liquid ◽  
Reaction Times ◽  
Aromatic Aldehydes ◽  
Environmentally Benign ◽  
H Nmr ◽  
Sonic Waves ◽  
Ft Ir ◽  
High Yields ◽  
Work Up ◽  
C Nmr

AbstractA simple, straightforward, and ultrasound-promoted method for the preparation of some highly functionalized tetrahydropyridines reported via pseudo five-component reaction of (hetero)aromatic aldehydes, different anilines, and alkyl acetoacetates in the presence of [N-CH2CO2H-3-pic]+HSO4−, as a novel ionic liquid, in green aqueous medium. The IL was synthesized utilizing simple and easily-handled substrates and characterized by FT-IR, 1H NMR, 13C NMR, GC-MASS, FESEM, EDX, and TGA/DTG techniques. The procedure contains some highlighted aspects which are: (a) performing the MCR in the presence of aqua and sonic waves, as two main important and environmentally benign indexes in green and economic chemistry, (b) high yields of products within short reaction times, (c) convenient work-up procedure, (d) preparing the new IL via simple substrates and procedure.

scholarly journals Synthesis of spiro[dihydropyridine-oxindoles] via three-component reaction of arylamine, isatin and cyclopentane-1,3-dione

2013 ◽  
Vol 9 ◽  
pp. 8-14 ◽  
Author(s):  
Yan Sun ◽  
Jing Sun ◽  
Chao-Guo Yan
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Room Temperature ◽  
The Other ◽  
Other Hand ◽  
Three Component Reaction ◽  
High Yields

A fast and convenient protocol for the synthesis of novel spiro[dihydropyridine-oxindole] derivatives in satisfactory yields was developed by the three-component reactions of arylamine, isatin and cyclopentane-1,3-dione in acetic acid at room temperature. On the other hand the condensation of isatin with two equivalents of cyclopentane-1,3-dione gave 3,3-bis(2-hydroxy-5-oxo-cyclopent-1-enyl)oxindole in high yields. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.

Facile synthesis of 4-substituted pyridines using grignard reagents

1982 ◽  
Vol 23 (38) ◽  
pp. 3935-3936 ◽  
Author(s):  
Kin-ya Akiba ◽  
Yuji Iseki ◽  
Makoto Wada
Keyword(s):  
Grignard Reagents ◽  
Facile Synthesis ◽  
Substituted Pyridines

Facile Synthesis of 2-Arylindoles through Plancher-Type Rearrangement of 3-Alkyl-3-Arylindolenines

Synlett ◽  
2017 ◽  
Vol 28 (15) ◽  
pp. 1994-1999
Author(s):  
Santhosh Chittimalla ◽  
Chennakesavulu Bandi ◽  
Vinod Gadi ◽  
Siva Gunturu
Keyword(s):  
Michael Addition ◽  
Facile Synthesis ◽  
Type C ◽  
High Yields

3-Alkylindoles on reaction with a cyclohexa-2,4-dien-1-one catalyzed by BF3·OEt2 gave the corresponding 3-alkyl-3-arylindolenines in high yields through a tandem Michael addition/aromatization sequence. In the presence of HCl, these indolenine derivatives underwent a facile Plancher-type C-3 to C-2 aryl rearrangement to deliver the corresponding 2-arylindoles.

scholarly journals A multi-colorimetric probe to discriminate between heavy metal cations and anions in DMSO–H2O with high selectivity for Cu2+ and CN−: study of logic functions and its application in real samples

RSC Advances ◽  
2021 ◽  
Vol 11 (47) ◽  
pp. 29466-29485
Author(s):  
Eunike Hamukwaya ◽  
Johannes Naimhwaka ◽  
Veikko Uahengo
Keyword(s):  
Heavy Metal ◽  
Schiff Base ◽  
Reaction Mechanism ◽  
High Selectivity ◽  
Colorimetric Probe ◽  
Real Samples ◽  
Heavy Metal Cations ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Logic Functions

A ditopic multi-colorimetric probe based on the phenylpridyl-thioic moiety (EN) was synthesized via a Schiff base reaction mechanism and characterized using 1H NMR and UV-vis spectroscopy.

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