P-Iodobenzyl bromide

Problem 16.60 Name and write the structures of the main organic products (a) H2C=XHCH2l heated with NaCN b) CHjCH CONH, heated with P,0, (c) p-iodobenzyl bromide reacted with CH,COOAg (d) nitration of benzamide. M... 

A soln. of p-iodobenzyl alcohol and 2,6-lutidine in chloroform added to 2,3,4,6-tetra-O-acetyl-a-D-mannopyranosyl bromide, and stored 24hrs. at room temp. 3,4,6-tri-0-acetyl-/ -D-mannopyranose 1,2- (p-iodobenzyl orthoacetate). Y 69%. F. e. s. M. Mazurek and A. S. Perlin, Can. J. Chem. A3, 1918 (1965) with tetra-n-butylammonium bromide in spm-collidine s. R. U. Lemieux and A. R. Morgan, Gan. J. Ghem. 43, 2199. 

Epoxidation is another important area which has been actively investigated on asymmetric phase transfer catalysis. Especially, the epoxidation of various (i.)-a,p-unsaturated ketones 68 has been investigated in detail utilizing the ammonium salts derived from cinchonine and cinchonidine, and highly enantioselective and diastereoselective epoxidation has now been attained. When 30 % aqueons H202 was utilized in the epoxidation of various a, 3-unsaturated ketones 68, use of the 4-iodobenzyl cin-choninium bromide 7 (R=I, X=Br) together with LiOH in Bu20 afforded the a,p-epoxy ketones 88 up to 92% ee,1641 as shown in Table 5. The O-substituted... 

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