CHLOROPHENYL ALLYL ETHER

Chloro allyldiisobulyl 4-Chlorophenol 1 moles of NaOH in THF then telluronium bromide added phenol telluronium mixture stirred (5h.) under Nj to give allyl 4-chlorophenyl ether, bromide... 

By contrast, 4-chlorophenol undenA ent etherificatbn when reacted in tetrahydrofuran solution containing 1 mole of sodium hydroxide with allyldiisobutyltelluronium bromide under nitrogen during 5 hours to give allyl 4-chlorophenyl ether in 86% yield (ref. 41). 

Typical procedure A mixture of p-chlorophenol (128 mg, 1 mmol), NaOH (40 mg, 1 mmol) and THF (10 mL) was stirred for 10 min allyldiisobutylteUuronium bromide (360 mg, 1 mmol) was then added. The reaction mixture was stirred for another 5 h at room temperature under nitrogen. Aqueous saturated NaHCOj solution was added and extracted with CH2CI2. The extract was dried over anhydrous MgS04 and concentrated in vacuo. The residue was chromatographed on sihca gel with 95 5 hexane-ethyl acetate as eluent to give a colourless oil of allyl p-chlorophenyl ether (145 mg, 86%). 

Jia, Zhou, and coworkers reported flow Claisen rearrangement without solvent [61]. The reaction of allyl p-chlorophenyl ether at 220 °C proceeded well with 24 min residence time to give 82% yield of product in a microflow system, while the same reaction in a batch reactor gave 14% yield of the product (Scheme 5.44). 

The SmCh-catalyzed electroreductive cleavage of allyl ethers (493) leading to (494) has been performed in a DMF-Bu4NBr-(Mg/Ni) system in the presence of SmCh (10 mol%) in an undivided cell (Scheme 171) [573]. A similar ether cleavage does not proceed in the cases of o-chlorophenyl or o-bromophenyl allyl ethers (495) and the reduction of the Ar— Cl... 

The synthesis of a variety of dihydrobenzofuranes can be accomplished via the Aryl SN1 mechanism. The acetone-sensitized irradiation of various o-chlorophenyl allyl ethers in polar solvents affords the aryl cation, which adds onto the tethered double bond following the 5-exo-trig mode leading to (dihydro)benzofurans. The reaction is solvent-dependent, and byproducts are also generally obtained. The best results are found when ethyl acetate is used. Depending on the substrate employed, the cation intermediate can yield products as a result of proton elimination or trapping by chloride ions (Scheme 10.54) [70],... 

Chlorophenyl allyl ether (p. 81) is placed in a flask equipped with a reflux condenser and a thermometer placed in the liquid. The liquid is heated to reflux until its temperature has risen to 256°. 

A mixture of 1 part by weight of p-chlorophenol, 1.1 parts of allyl bromide, 1.1 parts of potassium carbonate, and 1.3 parts of acetone is heated under reflux for 4 hours and then poured into water. The mixture is extracted with ether, and the ethereal solution is washed with dilute aqueous sodium hydroxide, then with water, dried over potassium carbonate, and distilled under vacuum. p-Chlorophenyl allyl ether is collected at 106-107°/12 mm., and the yield is quantitative. 

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