Reaction of 2-bromo-3,5-dimethyl-4H-thiopyran-4-one with nucleophiles. 1. Sodium hydroxide and sodium methoxide

1978 ◽  
Vol 43 (26) ◽  
pp. 4966-4968 ◽  
Author(s):  
F. H. Greenberg ◽  
Y. Gaoni
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Methoxide

Acridone studies. XIV. The selective demethylation of 2,3-Dimethoxy-10-methyl-9-oxoacridine-1,4-quinone by base

1975 ◽  
Vol 28 (6) ◽  
pp. 1351 ◽  
Author(s):  
JR Cowan ◽  
DKC Hodgeman ◽  
RH Prager
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Methoxide ◽  
Reaction Pathways ◽  
Methoxyl Group ◽  
Product Composition ◽  
Relative Extent ◽  
Kinetics Of

The selective demethylation of 2,3-dimethoxy-10-methyl-9-oxoacridine- 1,4-quinone by sodium hydroxide has been studied by following the change in product composition with hydroxide concentration, by measuring the relative extent of exchange at C2 and C3 with sodium methoxide[T], and by following the kinetics of the reaction in alkali. Reaction pathways are proposed to rationalize the observation that the C2 methoxyl group is replaced more readily in dilute alkali or on warming, but the C 3 methoxyl group is replaced in more concentrated alkali.

Synthesis of 2,2,4-Trimethyl-1,3-Pentanediol Monoisobutyrate

2014 ◽  
Vol 1033-1034 ◽  
pp. 76-80
Author(s):  
Xiang Jing Zhang ◽  
Peng Tao Wu ◽  
Zi Chao Jiang ◽  
Ting Ting Liu ◽  
Xiao Yang Gao ◽  
...  
Keyword(s):  
Reaction Time ◽  
Sodium Hydroxide ◽  
Calcium Hydroxide ◽  
Reaction Temperature ◽  
Sodium Methoxide ◽  
Sodium Ethoxide ◽  
Water Soluble ◽  
Orthogonal Experiments ◽  
Paint Industry ◽  
Green Additive

2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (CS-12) is a non-water-soluble diol ester and an emerging green additive, widely used in paint industry. It can be synthesized by isobutyraldehyde with alkali as catalyst. In this article, several catalysts were studied for the synthesis of CS-12, for example, sodium hydroxide, calcium hydroxide, the mixture of sodium hydroxide and calcium hydroxide, sodium methoxide, the solution of sodium methoxide and methanol, and sodium ethoxide. Sodium hydroxide was finally selected as the optimal catalyst for the reaction. The effect of the amount of catalyst, reaction temperature and reaction time on the reaction were investigated by orthogonal experiments. The final optimal conditions are as follows: the catalyst dosage is 2 %, the reaction temperature is 50 °C, the reaction time is 4h. Under these conditions, the conversion of isobutyraldehyde is 93.10%, the selectivity of target product is 92.98%.

Preparing Sodium Methoxide from Sodium Hydroxide by Reaction Coupling with Separation Processes

2014 ◽  
Vol 986-987 ◽  
pp. 101-105 ◽  
Author(s):  
Meng Xiong ◽  
Cheng Xi Wang ◽  
Dan Dan Shao
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Methoxide ◽  
Batch Reactor ◽  
Coupling Reaction ◽  
Sodium Hydroxide Concentration ◽  
Separation Processes ◽  
Reaction Phase ◽  
Different Temperatures ◽  
Reaction Coupling ◽  
Good Agreement

Preparing sodium methoxide by reacting sodium hydroxide with methanol was investigated. The chemical equilibrium constant was small. Removing water out of the reaction phase could drive the reaction to produce more sodium methoxide. The experiments were carried out at different temperatures and 1 atm in semi-batch reactor by liquid evaporating to remove water. The effects of initial sodium hydroxide concentration and liquid evaporating speed were discussed. A mathematical model coupling reaction with separation processes was built and the predicted results by the model were in good agreement with experiment results. The model provides useful information for industrial simulation.

Preparation of 2-Methoxytetrahydropyran-3-one from Halogenated Dihydro- and Tetrahydropyran Precursors

1973 ◽  
Vol 51 (20) ◽  
pp. 3354-3356 ◽  
Author(s):  
J. E. Roff ◽  
R. K. Brown
Keyword(s):  
Sodium Hydroxide ◽  
Good Yield ◽  
Sodium Methoxide ◽  
Aqueous Sodium Hydroxide ◽  
Cleavage Product ◽  
Ring Cleavage ◽  
Aqueous Sodium

The reaction of 5-halo-3,4-dihydro-2H-pyran with halogen and sodium methoxide gives in good yield the corresponding 3,3-dihalo-2-methoxytetrahydropyran. The latter, upon treatment with aqueous sodium hydroxide or sodium methoxide in methanol failed to provide 2-methoxytetrahydropyran-3-one but instead gave the 3-halo-2-methoxy-5,6-dihydro-2H-pyran. The ketone, 2-methoxytetrahydropyran-3-one was obtained by the treatment of 5-chloro-3,4-dihydro-2H-pyran with m-chloroperoxybenzoic acid followed by the addition of sodium methoxide.Attempts to prepare the 3,3-dibromo-2-methoxytetrahydropyran by the reaction of 3-bromo-2-methoxytetrahydropyran with bromine were unsuccessful, but gave the ring cleavage product, methyl 2,5-dibromopentanoate.

Preparation of trisodium O-monoalkyl and O-monoaryl diphosphates

2008 ◽  
Vol 62 (2) ◽  
Author(s):  
Fridrich Gregáň ◽  
Milan Melicherčík ◽  
Juraj Gregáň ◽  
Milan Remko
Keyword(s):  
Biological Activity ◽  
Ir Spectroscopy ◽  
Sodium Hydroxide ◽  
1H Nmr ◽  
Sodium Methoxide ◽  
31P Nmr ◽  
Current Work ◽  
Phosphoric Acids

AbstractTrisodium O-methyl, O-butyl, O-phenyl, and O-(4-nitrophenyl) diphosphates were synthesized from sodium dimethylamido-O-(2-cyanoethyl) phosphate and O-alkyl-and O-aryl phosphoric acids. While in the previously described method, sodium hydroxide was used for the preparation of O-phenyl diphosphate, in our current work, we present an improved protocol, where sodium methoxide is used to increase the yields of O-alkyl and O-aryl diphosphates. The structures of final compounds were determined by 1H NMR, 31P NMR, and IR spectroscopy. The sodium O-alkyl- and O-aryl diphosphate salts prepared by this method may be used for the study of biological activity of diphosphate analogues.

scholarly journals Switching the reaction pathways of electrochemically generated β-haloalkoxysulfonium ions – synthesis of halohydrins and epoxides

2015 ◽  
Vol 11 ◽  
pp. 242-248 ◽  
Author(s):  
Akihiro Shimizu ◽  
Ryutaro Hayashi ◽  
Yosuke Ashikari ◽  
Toshiki Nokami ◽  
Jun-ichi Yoshida
Keyword(s):  
Dimethyl Sulfoxide ◽  
Sodium Hydroxide ◽  
Sodium Methoxide ◽  
Reaction Pathways ◽  
Halocarbonyl Compounds

β-Haloalkoxysulfonium ions generated by the reaction of electrogenerated Br+ and I+ ions stabilized by dimethyl sulfoxide (DMSO) reacted with sodium hydroxide and sodium methoxide to give the corresponding halohydrins and epoxides, respectively, whereas the treatment with triethylamine gave α-halocarbonyl compounds.

Comparison of Acrylamide and Agar Gels by Freeze-Etching

1977 ◽  
Vol 35 ◽  
pp. 606-607
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe
Keyword(s):  
Electron Microscope ◽  
Sodium Hydroxide ◽  
Sodium Hypochlorite ◽  
Chromic Acid ◽  
Distilled Water ◽  
Thin Sheets ◽  
Acid Cleaning ◽  
Agar Gels ◽  
Freeze Etching ◽  
Water Cut

Thin sheets of acrylamide and agar gels of different concentrations were prepared and washed in distilled water, cut into pieces of appropriate size to fit into complementary freeze-etch specimen holders (1) and rapidly frozen. Freeze-etching was accomplished in a modified Denton DFE-2 freeze-etch unit on a DV-503 vacuum evaporator.* All samples were etched for 10 min. at -98°C then re-cooled to -150°C for deposition of Pt-C shadow- and C replica-films. Acrylamide gels were dissolved in Chlorox (5.251 sodium hypochlorite) containing 101 sodium hydroxide, whereas agar gels dissolved rapidly in the commonly used chromic acid cleaning solutions. Replicas were picked up on grids with thin Foimvar support films and stereo electron micrographs were obtained with a JEM-100 B electron microscope equipped with a 60° goniometer stage.Characteristic differences between gels of different concentrations (Figs. 1 and 2) were sufficiently pronounced to convince us that the structures observed are real and not the result of freezing artifacts.

Immunocytochemical localization of desmin and vimentin in chick embryonic myocardial cells

1990 ◽  
Vol 48 (3) ◽  
pp. 448-449
Author(s):  
Yukiko Sugi
Keyword(s):  
Sodium Methoxide ◽  
Intermediate Filament Protein ◽  
Chick Embryos ◽  
Immunocytochemical Localization ◽  
Myocardial Cells ◽  
Immunofluorescence Study ◽  
Immunofluorescent Localization ◽  
Rabbit Igg ◽  
Semithin Sections ◽  
Filament Protein

In cultured skeletal muscle cells of chick, one intermediate filament protein, vimentin, is primarily formed and then synthesis of desmin follows. Coexistence of vimentin and desmin has been immunocytochemically confirmed in chick embryonic skeletal musclecells. Immunofluorescent localization of vimentin and desmin has been described in developing myocardial cells of hamster. However, initial localization of desmin and vimentin in early embryonic heart has not been reported in detail. By quick-freeze deep-etch method a loose network of intermediate filaments was revealed to exist surrounding myofibrils. In this report, immunocytochemical localization of desmin and vimentin is visualized in early stages of chick embryonic my ocardium.Chick embryos, Hamburger-Hamilton (H-H) stage 8 to hatch, and 1 day old postnatal chicks were used in this study. For immunofluorescence study, each embryo was fixed with 4% paraformaldehyde and embedded in Epon 812. De-epoxinized with sodium methoxide, semithin sections were stained with primary antibodies (rabbit anti-desmin antibody and anti-vimentin antibody)and secondary antibody (RITC conjugated goat-anti rabbit IgG).

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