O-allyl phenol

CAS 1745-81-9 EINECS/ELINCS 217-119-0 Synonyms o-Allylphenol Phenol, o-allyl- Phenol, 2-(2-propenyl)-... 

Phenol acetate. See Phenyl acetate Phenol alcohol. See Phenol Phenol, o-allyl-. See 2-Allylphenol Phenol, 2-amino-. See o-Aminophenol Phenol, 3-amino-. See m-Aminophenol Phenol, 4-amino-. See p-Aminophenol Phenol, m-amino. See m-Aminophenol Phenol, 3-amino-2-chloro-6-methyl-. See 5-Amino-6-chloro-o-cresol... 

Claisen rearrangement (Section 24 13) Thermal conversion of an allyl phenyl ether to an o allyl phenol The rearrange ment proceeds via a cyclohexadienone intermediate... 

The discovery of the utility of the bis-chromone carboxylic acid derivative cromolyn sodium in the treatment of asthma and related allergies has led to an intensive, and thus far not very fruitful, effort to discover analogues which would show oral activity in contrast to the lead which must be administered by inhalation. Preparation of a typical analogue, proxicromil (63), starts with the O-allylated phenol 57. Claisen rearrangement leads to the corresponding C-allylated product 58. 

The rearrangement of an O-allyl ether (LXXV) to form the isomeric ortho allyl phenol (LXXVI)... 

Although palladium catalysts have played the most prominent role in this area, other metals have also been found to catalyze allylic etherification reactions, often providing complementary stereochemical outcomes. A few ruthenium catalyst systems have been used for the O-allylation of phenols,143,144 including an enantioselective version utilizing [Cp Ru(MeCN)3]PF6 that provides promising ee s, albeit with diminished control of regioselectivity (Equation (25)).145... 

Some allyl phenyl ethers with an alkyl substituent on the end carbon of the allyl group rearrange to give the normal ortho-Claisen product together with another isomeric O-allyl phenol. The latter, formed by the rearrangement of the normal product, has been established. This is called abnormal Claisen rearrangement, is illustrated by the following example. 

The cationic complex [Ni(bpy)3](BF4)2 is a good catalyst for the electroreductive cleavage of the C—O (allyl) bond of allyl ethers, affording parent alcohols or phenols. The Ni(II)-catalyzed electroreductive deprotection of allyl ethers is found to proceed in a DMF-Bu4NBp4-(Mg) system. For... 

The ring closure of o-allyl phenols has been extended to the synthesis of several other types of fused furans. 

Synthesis of 2-(1-Hydboxyalkyl)-2,3-dihydrobenzofttrans fbom o-Allyl Phenols (168) AND... 

The allyl ethers of phenols may be converted via a Claisen rearrangement to o-allyl derivatives and thence to the benzo[6]furans. The products of addition of bromine to the o-allylphenols give good yields of the heterocycle on prolonged heating with alkali, but the photochemical rearrangement of O-allylphenol is not so effective. 

As reported in the literature synthesis, the starting phenol may be converted to the corresponding allyl ether by reaction with allyl bromide in the presence of base. This step was accomplished in 80% yield. Heating the allyl ether yields the o-allyl phenol. 

The removal of the O-allyl group from 326 was readily effected with catalytic rhodium trichloride in refluxing ethanol and was accompanied by the spontaneous cyclization of the intermediate phenol to provide the cis-hydrodibenzo-... 

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