Ethers rearrangement

Linalool can be converted to geranyl acetone (63) by the CarroU reaction (34). By transesterification with ethyl acetoacetate, the intermediate ester thermally rearranges with loss of carbon dioxide. Linalool can also be converted to geranyl acetone by reaction with methyl isopropenyl ether. The linalyl isopropenyl ether rearranges to give the geranyl acetone. 

AHyl phenyl ethers rearrange cleanly at high temperatures, producing o-aHyl phenols or -aHylphenols if both ortho positions are blocked. This reaction is called the Claisen rearrangement (10). 

Benzylenol ethers rearrange in an apparently similar fashion via photolytic fission of the benzyl-oxygen bond and subsequent recombination steps. Irradiation in quartz of a cyclohexane solution of 3-benzyloxycholesta-3,5-diene (250) leads to 23% (251), 13% (252) [presumably formed from (251) during workup] and 10% (253). ... 

Allyl vinyl ethers have been prepared using the ylide (101) but only from non-enolizable carbonyl compounds. The ethers rearrange on heating to give a-allyl aldehydes, e.g. (102). 

Cyclopropane 87, obtained from n-butyl vinyl ether, rearranges to dihydrofuran 88 only at elevated temperature, and also partly during work-up on silica gel113). The complete conversion of 87 into veratrole by the action of HCl/CH3OH gave rise to the analogous two-step synthesis of hydrourushiol monomethyl ether from l-diazo-3,3-dimethoxy-2-nonadecanone 89113). Ether cleavage of the product yields hydrourushiol, one of the vesicant components of, inter alia, poison ivy. 

There is much more left to be done in the area of catalytic RCM. It is likely that many elegant and creative uses of catalytic RCM are in the making. Judging by the related developments in recent years, it is also likely that catalytic RCM will influence positively the development of numerous other ongoing metal-catalyzed or uncatalyzed reactions. The advent and utility of complexes la, lb and 2 will undoubtedly inspire organic chemists to devise new and useful transformations, where these transition metal systems are effectively utilized (e.g., styrenyl ether rearrangements) [40]. 

Wittig ether rearrangement org chem The rearrangement of benzyl and alkyl ethers when reacted with a methylating agent, producing secondary and tertiary alcohols. vid-lk e-thor 3,ran -m3nt ... 

Methyl-2-ethyl butyl ether (Rearranged product)... 

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