scholarly journals A versatile method for the N, N-dialkylation of aromatic amines via Grignard reactions on N,N-bis(benzotriazolylmethyl)arylamines

1990 ◽  
Vol 68 (3) ◽  
pp. 456-463 ◽  
Author(s):  
Alan R. Katritzky ◽  
Stanislaw Rachwal ◽  
Jing Wu
Keyword(s):  
Alkyl Group ◽  
Aromatic Amines ◽  
Grignard Reagents ◽  
Grignard Reaction ◽  
Aryl Ring ◽  
Alkyl Groups ◽  
Grignard Reactions ◽  
Stepwise Procedure ◽  
High Yields

Grignard reactions of N,N-bis(benzotriazolylmethyl)arylamines afford the corresponding N,N-dialkylarylamines in high yields. Electron-releasing substituents on the aryl ring facilitate the reaction. Arylamines are N,N-dialkylated with two different alkyl groups by a stepwise procedure: N-benzotriazolylmethylation of an amine followed by a Grignard reaction to introduce the first alkyl group, and repetition of the same procedure to introduce the second alkyl group. Grignard reagents derived from 1,4-dihalobutane, upon reaction with N,N-bis(benzotriazolylmethyl)arylamines, give the corresponding N-aryl-hexahydroazepines together with acyclic products. Keywords: azepine, tertiary arylamines.

Stereospecific Grignard reactions of cholesteryl 1-alkenesulfinate esters: Application of the Andersen Protocol to the preparation of non-racemic α,β-unsaturated sulfoxides

2003 ◽  
Vol 81 (6) ◽  
pp. 423-430 ◽  
Author(s):  
Rick R Strickler ◽  
John M Motto ◽  
Craig C Humber ◽  
Adrian L Schwan
Keyword(s):  
Ester Group ◽  
Grignard Reagents ◽  
Grignard Reaction ◽  
Substitution Reactions ◽  
Reaction Conditions ◽  
Enantiomerically Pure ◽  
Sulfinate Esters ◽  
Grignard Reactions

Enantiomerically enriched α,β-unsaturated sulfinate esters of (–)-cholesterol undergo stereospecific substitutions at sulfur when treated in benzene at 6°C with Grignard reagents. Sulfoxides with ees of 85–99.5% are obtained when enantiopure sulfinates are used. The substitution reactions proceed with inversion of sulfur configuration. Enantiomerically pure cholesteryl (E)-2-carbomethoxyethenesulfinate is not a suitable reactant under the Grignard reaction conditions. It is suggested that the ester group induces unwanted reactions significantly lowering both the yield and sulfur stereogenicity.Key words: sulfinate, sulfoxide, Grignard reagents, stereospecific, unsaturated.

Alkyl 1-[2-(oxido anion)-, 3-, 4-, 5-alkyl substituted]phenyl ketyl radicals

1979 ◽  
Vol 44 (6) ◽  
pp. 1731-1741 ◽  
Author(s):  
Andrej Staško ◽  
Ľubomír Malík ◽  
Alexander Tkáč ◽  
Vladimír Adamčík ◽  
Eva Maťašová
Keyword(s):  
Electron Donor ◽  
Unpaired Electron ◽  
Grignard Reagents ◽  
Slight Effect ◽  
Benzene Nucleus ◽  
Alkyl Groups ◽  
Splitting Constant

Reactions of R2,R3-alkyl substituted 2-hydroxybenzenecarboxylic acids 2-HO-C6H2R2-COOH with Grignard reagents R1MgBr in the presence of nickel give stable aryl alkyl ketyl radicals 2-O--R2-, R3-C6H2-CO--R1 where R1 = CH3, C2H5, C2D5, n-C3H7 and R2,R3 = CH3, C2H5, i-C3H7, t-C4H9. The β protons of ketyl group are equivalent (splitting constant 1.25 mT) and non-equivalent (splitting constants within 0.5 to 1.5 mT) for R1 = methyl and other alkyl groups, respectively. Interaction of the γ protons with the unpaired electron was only observed in the case of R1 = n-propyl (splitting constants about 0.07 mT). The substituents R1 have but slight effect on values of splitting constants of the protons in R2,R3 and vice versa. Also splitting constants of the benzene nucleus (a4H = 0.55 mT, a6H = 0.44 mT) are only slightly affected by the substituents R1,R2,R3, which indicates dominant electron-donor effect of the oxido-anion group eliminating the relatively smaller contributions of the alkyl substituents.

Efficient Copper-Catalysed Synthesis of Carbazoles by Double N-Arylation of Primary Amines with 2,2′-Dibromobiphenyl in the Presence of Air

Synlett ◽  
2021 ◽  
Author(s):  
Tran Quang Hung ◽  
Tuan Thanh Dang ◽  
Peter Langer ◽  
Ha Nam Do ◽  
Nguyen Minh Quan ◽  
...  
Keyword(s):  
Aromatic Amines ◽  
Aliphatic Amines ◽  
Primary Amines ◽  
Coupling Reactions ◽  
Carbazole Derivatives ◽  
High Yields

AbstractAn efficient Cu-catalyzed synthesis of carbazole derivatives is reported, which proceeds by double C–N coupling reactions of 2,2′-dibromobiphenyl and amines in the presence of air. The reaction is robust, proceeds in high yields, and tolerates a series of amines including neutral, electron-rich, electron-deficient aromatic amines and aliphatic amines.

Rapid and Green One-Pot Synthesis of Novel 2-(4-Hydroxy-2-oxo-2H-chromen-3-yl)-2-(arylamino)-1H-indene-1,3(2H)-diones

2021 ◽  
Vol 18 ◽  
Author(s):  
Abolfazl Olyaei ◽  
Zahra Ghahremany ◽  
Madieh Sadeghpour
Keyword(s):  
Aromatic Amines ◽  
Low Cost ◽  
Guanidine Hydrochloride ◽  
Reaction Times ◽  
Solvent Free ◽  
One Pot ◽  
Solvent Free Conditions ◽  
The One ◽  
High Yields ◽  
Work Up

: A green and efficient protocol was developed for the one-pot three-component synthesis of novel 2-(4-hydroxy-2-oxo-2H-chromen-3-yl)-2-(arylamino)-1H-indene-1,3(2H)-dione derivatives by the reaction of 4-hydroxycoumarin, ninhydrin and aromatic amines in the presence of guanidine hydrochloride as an organocatalyst under solvent-free conditions. The present approach offers several advantages such as low cost, simple work-up, short reaction times, chromatography-free purification, high yields and greener conditions.

The Hantzsch pyrrole synthesis

1970 ◽  
Vol 48 (11) ◽  
pp. 1689-1697 ◽  
Author(s):  
M. W. Roomi ◽  
S. F. MacDonald
Keyword(s):  
Carboxylic Acids ◽  
Ethyl Acetoacetate ◽  
Alkyl Group ◽  
Ethyl Esters ◽  
Hantzsch Synthesis ◽  
Butyl Esters ◽  
Alkyl Groups

Ethyl esters of 2-alkyl- and 2,4-dialkylpyrrole-3-carboxylic acids are obtained generally by extensions of the Hantzsch synthesis, benzyl and t-butyl esters when the 2-alkyl group is methyl. Hemopyrrole is obtained from butanal and ethyl acetoacetate in three steps. Pyrroles bearing higher alkyl groups or carbobenzoxy groups are reductively alkylated like the corresponding methylpyrroles and carbethoxy derivatives; t-butyl esters do not survive.

scholarly journals Cytotoxicity against HL60 Cells of Ficifolidione Derivatives with Methyl, n-Pentyl, and n-Heptyl Groups

Molecules ◽  
2019 ◽  
Vol 24 (22) ◽  
pp. 4081
Author(s):  
Hisashi Nishiwaki ◽  
Megumi Ikari ◽  
Satomi Fujiwara ◽  
Kosuke Nishi ◽  
Takuya Sugahara ◽  
...  
Keyword(s):  
Insecticidal Activity ◽  
Alkyl Group ◽  
Caspase 3 ◽  
Biological Activities ◽  
Mosquito Larvae ◽  
Leukaemia Cell ◽  
Leukaemia Cell Line ◽  
Hl60 Cells ◽  
Flow Cytometric ◽  
Alkyl Groups

Ficifolidione, a natural insecticidal compound isolated from the essential oils of Myetaceae species, is a spiro phloroglucinol with an isobutyl group at the C-4 position. We found that ficifolidione showed cytotoxicity against cancer cells via apoptosis. Replacement of the isobutyl group by n-propyl group did not influence the potency, but the effect of the replacement of this group by a shorter or longer alkyl group on the biological activity remains unknown. In this study, ficifolidione derivatives with alkyl groups such as methyl, n-pentyl, and n-heptyl group—instead of the isobutyl group at the C-4 position—were synthesized to evaluate their cytotoxicity against the human promyelocytic leukaemia cell line HL60 and their insecticidal activity against mosquito larvae. The biological activities of their corresponding 4-epimers were also evaluated. As a result, the conversion of the isobutyl group to another alkyl group did not significantly influence the cytotoxicity or insecticidal activity. In HL60 cells treated with the n-heptyl-ficifolidione derivative, the activation of caspase 3/7 and the early stages of apoptosis were detected by using immunofluorescence and flow cytometric techniques, respectively, suggesting that the cytotoxicity should be induced by apoptosis even though the alkyl group was changed.

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