2.6- Dichlorobenzyl ether

CF3OSO2F or CH3OSO2F, PhSCH3, CF3CO2H, 0°, 30 min, 100% yield. Thioanisole suppresses acid-catalyzed rearrangement of the benzyl group to form 3-benzyltyrosine. The more acid-stable 2,6-dichlorobenzyl ether is cleaved in a similar manner. 

In the last case, nit-selective formation of 2,5-disubstituted tetrahydrofurans was achieved by protecting the 0-nucleophile with a bulky group of carefully chosen electrofugal properties43. When the 2,6-dichlorobenzyl ether rac-9 was treated with iodine, the diastereomeric cyclization products rac-10 were obtained in a (aS,2S)/(xR,2R) ratio as high as 50 1. 

Dichlorobenzyl Ether 2,6-Cl2C6H3CH20R and 2,4-Dichlorobenzyl Ether 2,4-Cl2C6H3CH20R... 

As with the 2,6-dichlorobenzyl ether the electron-withdrawing chlorine atoms confer greater acid stability to this group than the usual benzyl group. It is cleaved by hydrogenolysis (Pd-C, H2). ... 

Muscarine 5, one of the active ingredients in the toadstool fly agaric Amanita muscaria), contains a 2,3,5-trisubstituted tetrahydrofuran structure. A number of stereocontrolled syntheses have been worked out for muscarine. One of these starts with methyl vinyl ketone [16] and cyclizes stereoselec-tively the appropriately substituted <5-unsaturated 2,6-dichlorobenzyl ether 3 with iodine ... 

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