Some Organic Reactions Catalyzed By Oxa-polyfluoroalkane Sulfonic Acid And It's Salts

In this thesis, two parts of work are mainly involved, including some important organic reactions catalyzed by polyfluoro or perfluoroalkanesulfonic acid or their salts and the synthesis of series of chiral sulfonamide ligands derived from L-proline. Esterification of carboxylic acids with alcohols has been recognized as one of the most important unit reactions in organic synthesis. In this thesis, the 3-oxa-polyfluoropentane sulfonic acid and it's ammonium salts were synthesized. Then the direct estedfication of carboxylic acids with equimolar alcohols catalyzed by catalytic amount of this superacid and it's ammonium salts under mild conditions were studied. In this study, our works were focused on the esterification catalyzed by 3-oxa-polyfluoropentane sulfonic acid finally due to it's high efficiency and simple operation. Under the catalysis of 3-oxa-polyfluoropentane sulfonic acid (1 mol%), the esterification of various kinds of carboxylic acids and alcohols gave good to high yields (67-99%).The copper(II) 3-oxa-polyfluoropentanesulfonate was prepared and the Friedel-Crafts acylation catalyzed by catalytic amount of the copper salts was studied. According to the results of the experiment, copper(II)3-oxa-polyfluoropentanesulfonate was found to be an efficient Friedel- Crafts acylation catalyst for aromatic compounds which were activated by electron-donated substituted groups. Mediate to good yields (65-96%) were obtained. The catalyst can be recovered.Acetylation of alcohols and phenols is one of the most important manipulations in organic synthesis and provides a widely used means for protecting hydroxyl group. Bis(perfluoroalkylsulfonyl)amide lithium is another type of Lewis superacid. In this thesis, we have studied the acetylation of alcohols and phenols which was catalyzed by Bis(perfluoroalkylsulfonyl) amide lithium under solventless and mild conditions. Firstly, the acetylation of alcohols and phenols catalyzed by bis (trifluoromethanesulfonyl) amide lithium was investigated, and excellent yields (84-100%) were obtained. In order to overcome the drawback of inconvenient recovery of bis (trifluoromethanesulfonyl) amide lithium, The long fluorous ponytailbis (perfluorooctanesulfonyl) amide lithium was synthesized. Then it was used as the catalyst to catalyzed the acetylation reaction under the same conditions as those of bis(trifluoromethanesulfonyl) amide. Excellent yields (86-100%) were obtained. The catalyst can be recovered completely through simple operation, after being dried in vaccum; the catalyst can be reused without any loss of activity.Carbon-carbon bond forming reactions are most important transformations in organic synthesis. Among them, the addition of allymetallic reagents to imines is one of the most important approaches. In this thesis, the one-pot reaction of aldehydes, amines and tributylallylstannane catalyzed by Ytterbium (III) 3-oxa-polyfluoropentanesulfonate/benzoic acid under mild conditions to furnish homoallylic amines were studied. Excellent yields (90-99%) were obtained and several of homoallylic amines were synthesized by this method. In addition, the mechanism of this type reaction was discussed simply.To find and synthesize high selective chiral ligand is an important challenge in the field of asymmetric synthesis. In this thesis, the synthesis of series of chiral sulfonamide ligands which were derived from L-proline is our another part of work. From L-proline, we have synthesized the target chiral ligands (6-5a-i) in four steps.