scholarly journals First and efficient synthesis of 4-[((3,4-dihydroxybenzoyl)-oxy)methyl]-phenyl-β-D-glucopyranoside, an antioxidant from Origanum vulgare

2016 ◽  
Vol 81 (1) ◽  
pp. 23-28
Author(s):  
Yu-Wen Li ◽  
Cui-Li Ma
Keyword(s):  
Phase Transfer ◽  
Phase Transfer Catalyst ◽  
Efficient Synthesis ◽  
Origanum Vulgare ◽  
Triethylbenzylammonium Chloride ◽  
Polyphenolic Glycoside ◽  
Hydroxybenzyl Alcohol ◽  
Methyl Phenyl

4-(3,4-Dihydroxybenzoyloxymethyl)phenyl-O-?-D-glucopyranoside (DBPG, 1 ), a polyphenolic glycoside previously isolated from Oregano(Origanum vulgare L.) in 0.08% isolated yield, was synthesized in five chemical steps with 41.4% overall yield. First, 4-(hydroxymethylphenyl)-2,3,4,6-tetra-O-acetyl-b-D-glucopyranoside 4 was obtained in 53.2% yield by selective glycosylation of 4-hydroxybenzyl alcohol 3 with 2,3,4,6-tetra-O-acetyl-?-D-glucopyranosyl bromide 2 in a mixture of chlorobenzene and aqueous CsOH using triethylbenzylammonium chloride (TEBAC) as a phase transfer catalyst. Then, this product was esterified with 3,4-diacetoxylbenzoyl chloride 7 to generate 4-(3,4-diacetoxybenzoyloxy-methyl) phenyl 2,3,4,6-tetra-O-acetyl-b-D-glucopyranoside 8 in 95% yield. Finally, selectively global deacetylation of 8 was performed in a mixture of dibutyltin oxide and methanol under reflux to afford 1 in 94.8% yield.

Efficient Synthesis of Chromones with Alkenyl Functionalities by the Heck Reaction

2010 ◽  
Vol 63 (11) ◽  
pp. 1582 ◽  
Author(s):  
Tamás Patonay ◽  
Attila Vasas ◽  
Attila Kiss-Szikszai ◽  
Artur M. S. Silva ◽  
José A. S. Cavaleiro
Keyword(s):  
Heck Reaction ◽  
Halogen Atom ◽  
Phase Transfer ◽  
Bromine Atom ◽  
Tetrabutylammonium Bromide ◽  
Phase Transfer Catalyst ◽  
Efficient Synthesis ◽  
Terminal Alkenes

The usefulness of the Heck reaction in the field of chromones has been demonstrated. Bromochromones with the halogen atom in their rings A and B were reacted with various terminal alkenes to give hitherto unknown alkenyl‐substituted chromones. Reactivity of the substrates was found to markedly depend on the position of the bromine atom. Under phosphine‐free conditions using a phase‐transfer catalyst additive (tetrabutylammonium bromide), shorter reaction periods and usually higher yields were obtained.

Reactions of (phenylethynyl)sulfones with tricyclo[4.1.0.02,7]heptanes

2013 ◽  
Vol 91 (6) ◽  
pp. 465-471 ◽  
Author(s):  
V.A. Vasin ◽  
Yu.Yu. Masterova ◽  
V.V. Razin ◽  
N.V. Somov
Keyword(s):  
Phase Transfer ◽  
Phase Transfer Catalyst ◽  
Sulfonyl Group ◽  
Thermal Initiation ◽  
Methyl Phenyl

Methyl-, phenyl-, p-chlorophenyl-, and p-tolyl(phenylethynyl)sulfones under photochemical or thermal initiation add to the central bicyclobutane C1–C7 bond of 1-R(H, Me, Ph)-tricyclo[4.1.0.02,7]heptanes anti-selectively, and form norpinic adducts containing a phenylethynyl group in a geminal to substituent R position, and an endo-oriented sulfonyl group in position 7. The corresponding ketones were prepared by the hydration of the anti-adducts by the method of Kucherov. The ketone with a methylsulfonyl substituent under reflux in toluene in the presence of KOH powder and the phase-transfer catalyst (TEBA-Cl) afforded the tricyclic sulfone.

Basic hydrolysis of cinnamyl chloride

1982 ◽  
Vol 47 (1) ◽  
pp. 290-295
Author(s):  
Libor Červený ◽  
Marie Křivská ◽  
Antonín Marhoul ◽  
Vlastimil Růžička
Keyword(s):  
Phase Transfer ◽  
Phase Transfer Catalyst ◽  
Cinnamyl Alcohol ◽  
Triethylbenzylammonium Chloride ◽  
Basic Hydrolysis ◽  
Hydrolysis Of

Basic hydrolysis of 3-chloro-1-phenyl-1-propene (cinnamyl chloride) to 3-phenyl-2-propen-1-ol (cinnamyl alcohol) and 1-phenyl-2-propen-1-ol was studied. The effects of the base type, presence of triethylbenzylammonium chloride as a phase transfer catalyst, and temperature were examined.

scholarly journals TETRAKIS[3,5-DI(F-METHYL)PHENYL]BORATE AS THE FIRST EFFICIENT NEGATIVELY CHARGED PHASE TRANSFER CATALYST. KINETIC EVIDENCES

1981 ◽  
Vol 10 (5) ◽  
pp. 579-580 ◽  
Author(s):  
Hiroshi Kobayashi ◽  
Takaaki Sonoda ◽  
Hidetoshi Iwamoto ◽  
Masaji Yoshimura
Keyword(s):  
Phase Transfer ◽  
Phase Transfer Catalyst ◽  
Methyl Phenyl

ChemInform Abstract: Efficient Synthesis of Sulfones Using Polysorbate-80 as Phase-Transfer Catalyst.

ChemInform ◽  
2010 ◽  
Vol 23 (5) ◽  
pp. no-no
Author(s):  
G. K. BISWAS ◽  
M. CHAKRABARTY ◽  
P. BHATTACHARYYA
Keyword(s):  
Phase Transfer ◽  
Phase Transfer Catalyst ◽  
Polysorbate 80 ◽  
Efficient Synthesis

scholarly journals Triton-B Mediated Efficient Synthesis of Thioxoimidazolidine-4,5-diones

2019 ◽  
Vol 32 (1) ◽  
pp. 183-186
Author(s):  
Ram Kishore ◽  
M. Kamboj ◽  
M. Shukla ◽  
Devdutt Chaturvedi
Keyword(s):  
Room Temperature ◽  
Phase Transfer ◽  
Oxalyl Chloride ◽  
Phase Transfer Catalyst ◽  
Efficient Synthesis

A simple, mild and efficient protocol for the synthesis of thioxoimidazolidine-4,5-diones (1-15) from substituted thiourea employing Triton-B/CS2 system has been discussed. The protocol described is an easy, efficient, nature-friendly method using cheap, easily available, less toxic reagents at room temperature. The synthesis involves the reaction between substituted thiourea in toluene and oxalyl chloride at room temperature using phase transfer catalyst Triton-B/CS2 system.

A Study on the Rearrangement of Dialkyl 1-Aryl-1-hydroxymethylphosphonates to Benzyl Phosphates

2020 ◽  
Vol 24 (4) ◽  
pp. 465-471 ◽  
Author(s):  
Zita Rádai ◽  
Réka Szabó ◽  
Áron Szigetvári ◽  
Nóra Zsuzsa Kiss ◽  
Zoltán Mucsi ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Room Temperature ◽  
Phase Transfer ◽  
One Pot ◽  
Substrate Dependence ◽  
Triethylbenzylammonium Chloride ◽  
One Step ◽  
The Pudovik Reaction ◽  
The One ◽  
Solid Liquid

The phospha-Brook rearrangement of dialkyl 1-aryl-1-hydroxymethylphosphonates (HPs) to the corresponding benzyl phosphates (BPs) has been elaborated under solid-liquid phase transfer catalytic conditions. The best procedure involved the use of triethylbenzylammonium chloride as the catalyst and Cs2CO3 as the base in acetonitrile as the solvent at room temperature. The substrate dependence of the rearrangement has been studied, and the mechanism of the transformation under discussion was explored by quantum chemical calculations. The key intermediate is an oxaphosphirane. The one-pot version starting with the Pudovik reaction has also been developed. The conditions of this tandem transformation were the same, as those for the one-step HP→BP conversion.

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