References
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- Ouchi , M. , Inoue , Y. , Kanzaki , T. and Hakushi , T. 1984 . J. Org. Chem. , 49 : 1408 We modified the procedure by using a reaction time of 24 hrs instead of 2 hrs at 0° and obtained a 97% yield of ditosylate (lit. 81%) without the necessity of using column chromatography for purification. The excess p-toluenesulfonyl chloride was removed from the reaction simply by washing with hexanes.
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