反应详情

Dimethylsulphoxonium methylide was prepared by the method described by Corey and Chaykovsky, loc. cit., from trimethylsulphoxonium chloride (25.7 parts) by treatment with sodium hydride (6.7 parts) in dry tetrahydrofuran. This ylide was converted into dimethylsulphoxonium p-toluenesulphonylmethylide by reaction with p-toluenesulphonyl fluoride (17.4 parts) using the method described by Truce and Madding, loc. cit. The toluenesulphonylmethylide was neutralised by the addition of 65% aqueous hexafluorophosphoric acid (49.5 parts) over 15 minutes, followed by concentration of the solution. The white solid which precipitated was filtered off, washed with water, and dried under vacuum to give 20 parts of the desired product (VI, R=p--CH3C6H4, R6 =H, R7 =R8 =CH3, q=t=1, Zt- =PF6-), mpt. 174°-5° C.; NMR (acetone -d6) 2.50 (s-3H), 4.23 (s-6H), 6.20 (s-2H), 7.5-8.2 (m-4H); IR (KBr disc) 3020, 3000, 2930, 2920, 1590, 1400, 1330, 1300, 1250, 1160, 1030, 940, 840, 750 cm-1 ; UV (ethanol) λmax 255 nm (data for product recrystallised from methanol).

1. customDimethylsulphoxonium methylide was prepared by the method
2. customThe white solid which precipitated
3. filtrationwas filtered off
4. washwashed with water
5. customdried under vacuum