C-Glycosylflavonoids. III. The Synthesis of 5,7,4'-Tri-O-methylvitexin (8-C-β-D-Glucopyranosyl-5,7,4'-trimethoxyflavone)

1979 ◽  
Vol 32 (11) ◽  
pp. 2483 ◽  
Author(s):  
RA Eade ◽  
H Pham
Keyword(s):  
Zinc Oxide ◽  
Acetic Anhydride ◽  
Sodium Hydroxide ◽  
Chemical Shifts ◽  
Selenium Dioxide ◽  
Aluminium Chloride ◽  
Anhydrous Aluminium Chloride

The reaction between 1,3,5-trimethoxybenzene and tetraacetyl-α-D-glucosyl bromide in the presence of zinc oxide gave β-D-glucopyranosyl-2,4,6-trimethoxybenzene tetraacetate (12). The tetraacetate (12) was converted by acetic anhydride and anhydrous aluminium chloride into 3-β-D- glucopyranosyl-2-hydroxy-4,6-dimethoxyacetophenone tetraacetate (15). Condensation of the acetophenone tetraacetate (15) with 4-methoxybenzaldehyde in the presence of sodium hydroxide gave 3'-β-D-glucopyranosyl-2'-hydroxy-4,4',6'-trimethoxychacone (6). Reaction of the chalcone (6) with selenium dioxide gave 8-C-β-D-glucopyranosyl-5,7,4'-trimethoxyflavone (5,7,4'-tri-O- methylvitexin)(10). The chemical shifts of the olefinic protons of chalcones are discussed.

Extractives of Australian timbers. XV. The synthesis of 7,4'-Di-O-methylbayin

1975 ◽  
Vol 28 (9) ◽  
pp. 2011 ◽  
Author(s):  
RA Eade ◽  
FJ Mcdonald ◽  
JJH Simes
Keyword(s):  
Acetyl Chloride ◽  
Selenium Dioxide ◽  
Aluminium Chloride ◽  
Authentic Material ◽  
Anhydrous Aluminium Chloride

The reaction between 2,6-dimethoxyphenylmagnesium bromide and tetraacetyl-α-D- glucosyl chloride gave mainly α-D-glucopyranosyl-2,6-dimethoxybenzene (8) and the β-isomer (9). The a-isomer (8) was readily converted by acids into the /?-isomer (9), whose structure was confirmed by comparison with authentic material prepared by the degradation of 7,4?-di-O-methylbayin. The reaction of the tetraacetate of (9) with acetyl chloride in the presence of anhydrous aluminium chloride gave 3-β-D-glucopyranosyl-2-hydroxy-4-methoxyacetophenone (11). Condensation of (11) with p-methoxybenzaldehyde gave the chalcone (15) which, on reaction with selenium dioxide, formed 7,4?-di-O-methylbayin (8-C-β-D- glucopyranosyl-7,4?-dimethoxyflavone) (5).

scholarly journals SYNTHESIS OF C-METHYL-4,10,16,22-TETRAMETHOXYCALIX[4]ARENE FROM PHENOL USING BF3-METHANOL AS THE CATALYST

2010 ◽  
Vol 5 (1) ◽  
pp. 58-65
Author(s):  
Jumina Jumina ◽  
Evi Triwulandari ◽  
Chairil Anwar
Keyword(s):  
Acetic Anhydride ◽  
Viscous Liquid ◽  
Acid Catalyst ◽  
Phenyl Ether ◽  
Aluminium Chloride ◽  
Proton Nuclear Magnetic Resonance ◽  
Yield Reduction ◽  
Colorless Liquid ◽  
Anhydrous Aluminium Chloride ◽  
Methyl Phenyl

   C-Methyl 4,10,16,22-tetramethoxycalix[4]arene has been synthesized from phenol. The reaction performed consisted of methylation of phenol, acetylation of methyl phenyl ether, reduction of p-methoxyacetophenone, and cyclization of p-methoxy-(1-hydroxyethyl)benzene to form C-methyl-4,10,16,22-tetramethoxycalix[4]-arene using BF3-methanol as the acid catalyst.  Methylation of phenol was done by reacting phenol with solution of NaOH to generate sodium phenoxide salt. This mixture was strirred at  reflux for 0.5 hours. Dimethyl sulphate was added and the reflux was continued for 2,5 hours. The product obtained was methyl phenyl ether, which was found as  a colorless liquid in 99.0% yield. Acetylation of methyl phenyl ether was carried out in chloroform using acetic anhydride as the acetylating agent and anhydrous aluminium chloride as the catalyst. The addition of acetic anhydride and anhydrous aluminium chloride was done in two portions. The first portion was 0.967 g of acetic anhydride and 1.4 g of anhydrous aluminium chloride. The second portion was 0.54 g of acetic anhydride and 0.6 g of anhydrous aluminium chloride. The product obtained was found as a reddish yellow liquid in 69.6% yield. Reduction of p-methoxyacetophenone as the acetylation product  was  done using NaBH4 in ethanol at reflux for 2.5 hours. From this reaction, p-methoxy-(1-hydroxyethyl)benzene was obtained as a brown viscous liquid in 44.9% yield. Cyclization of p-methoxy(1-hydroxyethyl)benzene was done using BF3-methanol as the acid catalyst for two days at room temperature. The product obtained from this cyclization was found as a brown very viscous liquid in 87.3% yield. Identification of reaction products were carried out using Infra Red (IR) Spectrophotometer, Proton Nuclear Magnetic Resonance (1H NMR) spectrometer and Gas Chromatography-Mass spectroscopy (GC-MS).       Keywords: synthesis, calix[4]arene, cyclization, and catalyst.

ortho-Diquaternary aromatic compounds. II. Synthesis and spectral properties of β,β′-dihydroxy-2,3-di-t-butylnaphthalene and related crowded aromatics

1969 ◽  
Vol 47 (23) ◽  
pp. 4313-4318 ◽  
Author(s):  
L. R. C. Barclay ◽  
G. R. Nixon ◽  
H. M. Foote ◽  
S. L. Barclay
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Aromatic Compounds ◽  
Spectral Properties ◽  
Bond Angle ◽  
Chemical Shifts ◽  
Dimethyl Ester ◽  
Selenium Dioxide ◽  
Hydride Reduction ◽  
Cyclic Compounds ◽  
Compression Effects

Cyclialkylation of naphthalene with 2,2,5,5-tetramethyltetrahydrofuranone yielded 2-keto-1,1,4,4-tetramethyl-1,2,3,4-tetrahydroanthracene (1). Selenium dioxide oxidation of 1 yielded the corresponding diketone (3) and periodate cleavage of 3 yielded 2,3-naphthalene-diisobutyric acid (4). Hydride reduction of the dimethyl ester (6) of 4 yielded the diol, β,β′-dihydroxy-2,3-di-t-butylnaphthalene (7). The relative chemical shifts of aromatic protons of 1,2,4,5-tetraalkylbenzenes containing gem dimethyls are rationalized in terms of compression effects exerted by the bulky ortho groups. Nuclear magnetic resonance and ultraviolet spectral results for the ortho di-t-butyl aromatic derivatives 4, 6, and 7 are compared to the model cyclic compounds 1 and anhydride (5) of 4 in terms of the strain caused by bond angle deformations in the side chains.

scholarly journals Synthesis of 3-Ferrocenyl Isocoumarins

2020 ◽  
Vol 36 (05) ◽  
pp. 976-979
Author(s):  
Neeta Sinha
Keyword(s):  
Spectral Analysis ◽  
Melting Point ◽  
Phosphoric Acid ◽  
Polyphosphoric Acid ◽  
Aluminium Chloride ◽  
Melting Point Determination ◽  
Anhydrous Aluminium Chloride ◽  
Point Determination ◽  
Derivatives Of

The derivatives of 3-ferrocenyl isocoumarin were synthesized by the condensation of substituted homothphalic anhydride with ferrocene using phosphoric acid or anhydrous aluminium chloride as cyclising agent. Substituted homophthalic acid did not condense with ferrocene so homophthalic acids were converted into their anhydride and then allowed to react with ferrocene in the presence of polyphosphoric acid or in the presence of anhydrous aluminium chloride using dichloromethane as the solvent to give 3-ferrocenyl isocoumarins. 7-Methoxy, 6-methyl, 5,7-dihydroxy, 6,7-dimethoxy and 5,7-dimethoxy derivatives of 3-ferrocenyl isocoumarin were synthesized. All the compounds were characterised by melting point determination, elemental and spectral analysis.

Effect of Calcium on the Solubility of Zinc Oxide in the Sodium Hydroxide Solution

2013 ◽  
pp. 257-263
Author(s):  
Chen Ai-liang ◽  
Xu Dong ◽  
Chen Xing-yu ◽  
Liu Xu-heng ◽  
Zhu Wei-xiong
Keyword(s):  
Zinc Oxide ◽  
Sodium Hydroxide ◽  
Sodium Hydroxide Solution ◽  
Hydroxide Solution

Adhesion of Rubber to Magnesium Alloys in the Presence of Nickel Branched Alkyl Carboxylates

2003 ◽  
Vol 76 (4) ◽  
pp. 1019-1030 ◽  
Author(s):  
K. Mori ◽  
X. Shi ◽  
H. Hirahara ◽  
Y. Oishi
Keyword(s):  
Aqueous Solution ◽  
Zinc Oxide ◽  
Magnesium Alloy ◽  
Aqueous Solutions ◽  
Sodium Hydroxide ◽  
Magnesium Alloys ◽  
Peel Strength ◽  
Magnesium Alloy Az31 ◽  
Rubber Compounds ◽  
Alkyl Carboxylates

Abstract The authors investigated the adhesion of rubber compounds containing nickel blanched alkyl carboxylate to surface treated magnesium alloys during curing. Ni i-octylate and Ni i-stearate were used as nickel branched alkyl carboxylate. Rubbers used in the study did not adhere at all to magnesium alloys, such as AZ91, AZ31, AZ 21, and M1 washed with acetone; not even in the presence of Ni i-octylate. Among numerous treating solutions, only sodium hydroxide aqueous solution was effective for adhesion of rubber to magnesium alloys. Adhesion of rubber to magnesium alloy AZ31 treated in 0.5M- sodium hydroxide aqueous solution for 10 min at 80 °C yielded high peel strength and a 100% rubber coverage. Peel strength and a 100% rubber coverage varied with the concentration of additives, such as curing accelerators, sulfur, zinc oxide and Ni-type adhesive accelerators. Ni branched alkyl carboxylates such as Ni i-octylate and Ni i-stearate were effective for accelerating the adhesion of rubber to magnesium alloys treated in sodium hydroxide aqueous solutions during curing. The authors postulate that Ni branched alkyl carboxylate acts to yield interface bonds between magnesium alloys and rubber or Ni-S-rubber linkage.

scholarly journals Development of a mathematical model for alkylation of m-cresol with α-methylstyrene using anhydrous aluminium chloride

2019 ◽  
Vol 54 (3) ◽  
pp. 195-202
Author(s):  
S Sultana ◽  
ASMS Arefin ◽  
M Shahruzzaman
Keyword(s):  
Mathematical Model ◽  
Polymeric Materials ◽  
Aluminium Chloride ◽  
Molar Ratio ◽  
High Yield ◽  
Practical Utilization ◽  
Anhydrous Aluminium Chloride ◽  
Chloride Catalyst ◽  
Ft Ir ◽  
Burman Design

Alkylaromatic compounds such as alkylphenols are the most wide spread and efficient material due to its broad practical utilization in different arenas including antioxidants, stabilizers for fuels, lubricating oils, polymeric materials and so on. In this work, (2-phenylpropan-2-yl) m-cresol with high yield was prepared from the reaction between m-cresol and _-methylstyrene in the presence of anhydrous aluminium chloride catalyst. Plackett-Burman design was applied for screening significant variables, such as, temperature, molar ratio of m-cresol to _-methylstyrene, time of reaction and amount of catalyst etc. to determine an optimum condition for the production of (2-phenylpropan-2-yl) m-cresol. Moreover, a 23 Yates pattern factorial design was used to develop a mathematical model to predict the yield of alkylation of m-cresol with _-methylstyrene. Analyses of the results revealed that temperature, molar ratio and amount of catalyst were the main effective variables. The products were characterized by FT-IR, UV-visible and 1H NMR spectroscopy. The adequacy of the suggested model was checked up. The experimental yields exhibited good agreement with the predicted yields designed by the mathematical model. Hence, (2-phenylpropan-2-yl) m-cresol has the potential to be used as an industrially important compound in various applications. Bangladesh J. Sci. Ind. Res.54(3), 195-202, 2019

Sign in / Sign up

Export Citation Format

Share Document