Easy synthesis of 7-alkylbicyclo[3.3.1]non-6-en-3-ones by silica gel-promoted fragmentation of 3-alkyl-2-oxaadamant-1-yl mesylates
作者:Pelayo Camps、Rachid El Achab、Merce` Font-Bardia、Diana Go¨rbig、Jordi Morral、Diego Mun˜oz-Torrero、Xavier Solans、Montserrat Simon
DOI:10.1016/0040-4020(96)00217-7
日期:1996.4
A synthesis of 7-alkylbicyclo[3.3.1]non-6-en-3-ones4b-f and 4j, k by reaction of the corresponding 3-alkyl-2-oxaadamant-1-yl mesylates3 with silica gel in methylene chloride at room temperature, is described. The method failed to give enones4a, g and the related compounds4l, m, what can be rationalized on mechanistic grounds.
Multiple chlorinations and arylations at the tertiary positions of adamantane are promoted by FeCl3-doped K10 montmorillonite in CCl4 or in aromatic solvents. The process, remarkably easy to implement, can be tailored to selective formation of monosubstituted 1-adamantyl derivatives or 1,3-disubstituted adamantanes. The process achieves alkylation at the meta- and para-positions of toluene leading