Iodomethyl benzene

A camphor-based 3-acyl-2-oxazolidinone has also been used for diastereoselective alkylations66. The A-acylated auxiliary 18 is prepared in three steps from 7,7-dimethyl-2-oxobicy-clo[2.2.1]heptane-l-carboxylic acid (ketopinic acid, 17)67. Deprotonation by lithium diiso-propylamide in tetrahydrofuran at — 78 °C and subsequent alkylation with activated halides [(bromo- or (iodomethyl)benzene, 3-bromo- or 3-iodopropene] furnished moderate to good yields of alkylation products in high diastereomeric ratios (>97 3 by H NMR). With added hexamethylphosphoric triamide the alkylation yields are increased and bromoalkanes also give satisfactory yields. The diastereomeric ratios are, however, much lower (d.r. 70 30 to 85 15)67. 

While increasing anion solvation by protic solvents has an accelerating effect on SnI reactions as described above, it is often a decelerating factor in Sn2 reactions. Thus, reaction (5-103) between (iodomethyl)benzene and radioactively labeled sodium iodide in acetone is clearly decelerated by the addition of protic solvents such as water, ethanol or phenol, as demonstrated in Fig. 5-16 [266]. 

The DT of acrylates (butyl acrylate and methyl acrylate) with alkyl iodides was reported by Gaynor et al. and Matyjaszewski et al in 1995. For instance, solution polymerization of butyl acrylate in benzene initiated by AIBN at 50 °C in the presence of 1-phenylethyl iodide provided poly(butyl acrylate) with 97% monomer conversion in 7.5 h and Mn = 19 SOOgmol" (close to Mn,theoredcai = 18000gmor ) (Scheme 15a). The PDI = 2.0 is large, indicating a rather low Cex value. Later on, 2-ethylhexyl acrylate and tert-butyl acrylate were also polymerized by DT in the presence of bis(iodomethyl)benzene or PS-I, respectively. ... 

Bromo-4 -hydroxyacetophenone, B-00508 1 -Bromo-4-(iodomethyl)benzene, B-00514 9-(Bromomethyl)acridine, B-00516... 

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