Complex carbon-carbon bond formation under environmentally benign conditions using hot-pressurize water and near critical water

In most organic transformations, toxic and environmentally hazardous solvents are used in large excess during the reaction as well as in the isolation and purification steps. This leads to a costly disposal process and an increased threat of accidental contamination or pollution of the environment. Therefore, the Green Chemistry Initiative was begun in the late 1980's to find new and more environmentally friendly processes. Herein is presented a brief description of Green Chemistry, the history and application of water as a solvent for organic transformations, and the results from current research to develop new processes in which water is used as the solvent in carbon-carbon bond formation reactions.; The McKillop Reaction has been adapted and optimized for not only the formation of an aryl-alkyl carbon-carbon bond, but also the closure of a second ring in near critical water to produce an isochromenone. This system has been targeted because they are the core of mitocidal (insecticidal) natural products and medicinal agents.; The Hajos reaction has been examined in near-critical water and hot-pressurized water. The first step of the process, a Michael addition, has been adapted to using microwave heating which has reduced the reaction time from 3 days to less than an hour. The entire three step process has also been adapted to near critical water conditions to give a racemic mixture of the enone product in one step. This enone product is an important intermediate in the synthesis of steroids. More information into the mechanism of this reaction was also obtained.; In an effort to synthesis compounds with other functional groups beside oxygen, Mannich type reactions were adapted to hot pressurized water conditions. Chiral imines were also synthesized in environmentally friendly conditions. These imines were used in stereoselective Mannich typed reactions in which diastereomeric excesses of 50+% were achieved.