Studies of the Grignard Reaction. II. Kinetics of the Reaction of Dimethylmagnesium with Benzophenone and of Methylmagnesium Bromide-Magnesium Bromide with Pinacolone

1962 ◽  
Vol 27 (2) ◽  
pp. 596-598 ◽  
Author(s):  
M. ANTEUNIS
1985 ◽  
Vol 40 (7) ◽  
pp. 990-995 ◽  
Author(s):  
◽  
Balkrishen Bhat ◽  
A. P. Bhaduri

Abstract Grignard reactions of 2-morpholino and 2-methylthio-3-cyanoquinoline, 2-chloro-3-cyanoquinoline, 2-chloro-3-cyano-6-methoxyquinoline and 2-chloro-3-cyano-7-methylquinoline with alkyl or aryl magnesium halides have been studied. It was found that 2-morpholino and 2-methylthio- 3-cyanoquinolines gave 1,4-addition products followed by rapid aromatisation. 2-Chloro-3- cyanoquinoline with alkyl magnesium halides furnished 1,4-addition products but with aryl magnesium halides 1,4- and 1,2-addition products were obtained. The cyano group of 4-aryl-2-chloro- 3-cyano-1,4-dihydroquinolines was found to participate in the Grignard reaction to yield 1,2- addition products. 2-Chloro-3-cyano-6-m ethoxyquinoline with alkyl and phenyl magnesium halides yielded exclusively 1,4-addition products. Similarly with p-m ethoxyphenyl magnesium bromide, 1,4-addition products were isolated which participated in the Grignard reaction to yield the expected adducts. Unlike the other chloroquinoline derivatives, 2-chloro-3-cyano-7-methylquinoline with alkyl magnesium halide formed 1 ,2-addition products but with aryl magnesium halides, 1,4-addition products were isolated. The 4-alkyl-2-chloro-3-cyano-l,4-dihydroquinolines were unstable as compared to their 4-aryl analogs. A couple of the Grignard reaction products were found to be unstable on activated surface.


Author(s):  
Saeed Fathi ◽  
Phill Dickens ◽  
Khosrow Khodabakhshi ◽  
Marianne Gilbert

A novel process using inkjet printing of molten materials to produce nylon 6 for additive layer manufacturing applications was investigated. Different reactive mixtures of molten caprolactam with activator and catalyst were characterized for physical properties to understand their jettability in an inkjet system. Although it was found that the surface tension and viscosity of all materials were within the range suitable for inkjet technology according to the literature, microcrystals of undissolved salt of the catalyst complex (caprolactam magnesium bromide) were found to influence melt supply behavior. The influence of the process on the catalyst microcrystal consistency and agglomeration beyond the jetting system was investigated for purged, deposited multiple droplets and also individual droplet samples using hot-stage polarized light microscopy. Quantitative image analysis showed that although microcrystal agglomeration occurred within the accumulated droplets due to kinetics of droplet impact, this however was much less than with the purged samples. A generally consistent content and dispersion of the microcrystals existed within the consecutively deposited droplets.


2010 ◽  
Vol 5 (2) ◽  
Author(s):  
Putu Indrayani ◽  
Aliefman Hakim

Abstrak : Sintesis 6-metil-2-hepten-4-ol diawali dengan pembentukan reagen Grignard isobutilmagnesium bromida pada 400C selama 1 jam, dilanjutkan dengan pembentukan garam alkoksi magnesium bromida pada 00C.Hidrolisis terhadap garam alkoksi magnesium bromida dengan larutan NH4Cl jenuh menghasilkan 6-metil-2-hepten-4-ol. Hasil sintesis kemudian diuji sifat fisiko-kimianya meliputi berat jenis, indeks bias serta identifikasi denganSpektrofotometer Inframerah (IR), Kromatografi Gas (GC) dan Kromatografi Gas-Spektrometer Massa (GC-MS). Hasil sintesis menghasilkan cairan beraroma manis segar, berwarna kekuningan, berat jenis 0,81529 g/mL, indeks bias 1,40830, kemurnian 66,07 % dan hasil 46,31 %. Karakter IR senyawa hasil sintesis menunjukkan vibrasi ulur O-H alkohol pada 3361 cm-1, vibrasi ulur C-OH pada 1049,2 cm-1, vibrasi ulur C=C pada 1676 cm-1 dan serapan 2956,7 dan 2920 cm-1 untuk vibrasi ulur C-H dalam CH 3 dan spektra massa dengan m/e 128 yang dicapai pada waktu retensi 6,284 menit. Data-data tersebut mendukung bahwa senyawa hasil sintesis adalah 6-metil-2-hepten-4-ol.Kata kunci : Sintesis, reaksi Grignard dan 6-metil-2-hepten-4-olAbstract : Synthesis of 6-methyl-2-hepten-4-ol was generated with formation of Grignard reagent Isobutylmagnesium bromide carried out at 400C for one hour, then formation of alcoxide salt magnesium bromide carried out at 00C. Alcoxide salt magnesium bromide were hydrolyzed by saturated NH4Cl solution producing 6-methyl-2-hepten-4-ol. Results were examined physically and chemically including density, refraction index, pure percentage and yield percentage were 0,81529 g/mL, 1,40830, 66,07 % and 46,31 % respectively. The IR characters showed stretching vibration of O-H group at 3361 cm-1, stretching vibration C-OH group at 1049,2 cm-1, stretching vibration C=C group at 1676 cm-1 and absorption of C-H in CH3 2956,7 and 2920 cm-1. Identification using GC-MS resulted spectra m/e 128 at time retention 6,284 minutes. The proven data indicated that the resulted compound was 6-methyl-2-hepten-4-ol.Keywords : synthesis, Grignard reaction and 6-methyl-2-hepten-4-ol


Author(s):  
Csilla Sepsey Für ◽  
Eszter Judit Horváth ◽  
Áron Szigetvári ◽  
Miklós Dékány ◽  
László Hazai ◽  
...  

Abstract: An extended compound library of spiro[cycloalkane-pyridazinones] with high Fsp3 character is targeted. There are two possibilities to improve the physicochemical parameters of a drug candidate molecules or building blocks, either to replace the aromatic systems with bioisoster heteroaromatic moieties, e.g. with one or two nitrogen containing ring systems (pyridines, pyridazines, pyrimidines, etc.), or to increase the Fsp3 character of the compounds. Using a new synthetic ap-proach, the Grignard reaction of 2-oxaspiro[4,5]decane-1,3-dione and 2-oxaspiro[4,4]nonane-1,3-dione with p-halophenyl- or p-alkylphenyl-magnesium bromide resulted in the formation of the corresponding 2-oxoethyl-cycloalkanecarboxylic ac-ids, which served as starting materials for the formation of pyridazinone with hydrazine or phenylhydrazine. The pyridazi-nones obtained were alkylated with methyliodide or benzylbromide. 16 Novel 4-tolyl- or 4-halophenyl-2,3-diazaspiro[5.5]undec-3-en-1-one and 4-tolyl- or 4-halopyhenyl-7,8-diazaspiro[4.5]dec-8-en-6-one, and their N-methyl, N-benzyl, and N-phenyl derivatives were synthetized.The physicochemical parameters and the Fsp3 character of the novel compounds obtained were studied. A few of them showed excellent logP and clogP values, but introduction of further phe-nyl group seemed to be disadvantageous


1974 ◽  
Vol 52 (22) ◽  
pp. 3784-3786 ◽  
Author(s):  
Janet E. Forrest ◽  
Ronald A. Heacock ◽  
Thomas P. Forrest

The reaction of 3,4-methylenedioxybenzonitrile (2) with ethyl magnesium bromide gives products resulting from opening of the methylenedioxy ring, namely 4-hydroxy-3-n-propoxypropiophenone (3) and 3-hydroxy-4-n-propoxypropiophenone (4) in addition to the expected product 3,4-methylenedioxypropiophenone (1). The isomeric hydroxy-n-propoxy ketones were differentiated on the basis of their spectroscopic properties.


2008 ◽  
Vol 61 (3) ◽  
pp. 168 ◽  
Author(s):  
Richard C. Foitzik ◽  
Steven E. Bottle ◽  
Jonathan M. White ◽  
Peter J. Scammells

1,1,3,3-Tetraalkylisoindolines are important intermediates in the preparation of stable nitroxides, such as 1,1,3,3-tetramethylisoindolin-2-oxyl, 1, and 1,1,3,3-tetraethylisoindolin-2-oxyl, 2. The limiting step in their preparation is the Grignard reaction between N-benzylphthalimide and the appropriate alkyl magnesium bromide, which typically proceeds in yields of ~28–40%. A microwave-assisted variation of this reaction has been optimized to give improved yields and reduced reaction times (45–60% and 2 h, respectively).


2003 ◽  
Vol 68 (26) ◽  
pp. 9933-9937 ◽  
Author(s):  
Ants Tuulmets ◽  
Binh T. Nguyen ◽  
Dmitri Panov ◽  
Meeri Sassian ◽  
Jaak Järv

Author(s):  
J. F. DeNatale ◽  
D. G. Howitt

The electron irradiation of silicate glasses containing metal cations produces various types of phase separation and decomposition which includes oxygen bubble formation at intermediate temperatures figure I. The kinetics of bubble formation are too rapid to be accounted for by oxygen diffusion but the behavior is consistent with a cation diffusion mechanism if the amount of oxygen in the bubble is not significantly different from that in the same volume of silicate glass. The formation of oxygen bubbles is often accompanied by precipitation of crystalline phases and/or amorphous phase decomposition in the regions between the bubbles and the detection of differences in oxygen concentration between the bubble and matrix by electron energy loss spectroscopy cannot be discerned (figure 2) even when the bubble occupies the majority of the foil depth.The oxygen bubbles are stable, even in the thin foils, months after irradiation and if van der Waals behavior of the interior gas is assumed an oxygen pressure of about 4000 atmospheres must be sustained for a 100 bubble if the surface tension with the glass matrix is to balance against it at intermediate temperatures.


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