Camphorsulfonic acid monohydrate

Camphorsulfonic acid monohydrate Bicyclo[2.2.1]heptane-1-methanesulfonic acid, 7,7-dimethyl-2-oxo-, ( )- (9) (5872-08-2)... 

Fisher Certified A.C.S. formaldehyde solution is used as received. Aldrich Chemical Company, Inc., camphorsulfonic acid monohydrate is recrystallized from ethyl acetate prior to use. 

Camphorsulfonic acid monohydrate Bicyclo[2.2.1]heptane-1-methanesulfonic acid,... 

The best known member among the various classes of these iodanes is undoubtedly [hydroxy(tosyloxy)iodo]benzene (HTIB), sometimes called Koser s reagent. It is prepared readily from (diacetoxyiodo)benzene and p-toluenesul-fonic acid monohydrate in acetonitrile. The same method using p-nitroben-zenesulfonic acid or 10-camphorsulfonic acid leads to the corresponding sul-fonyloxy analogs [41,42]. Of special interest are some iodanes of this type coming from a chiral ether. Their preparation was effected by direct oxidation with sodium perborate and the isolated diacetoxy derivatives were separately treated with p-toluenesulfonic acid in acetonitrile (Scheme 8) [43]. 

In the carbohydrate series, acetates can be cleaved selectively in the presence of benzoates [Scheme 4.329] and p-bromobcnzoates using p-toluenesulfonic acid monohydrate (1 equivalent per acetate) in dichloromethane-methanol (9 1) at 4 °C in 7 h or room temperature in 24 h.616 No benzoyl migration is observed. The method also works in comparable yield with camphorsulfonic acid although the reaction takes 2 days at 40 °C and 3 days at room temperature. 

---