|Budget Amount *help
¥6,800,000 (Direct Cost : ¥6,800,000)
Fiscal Year 1993 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1992 : ¥2,900,000 (Direct Cost : ¥2,900,000)
Fiscal Year 1991 : ¥3,100,000 (Direct Cost : ¥3,100,000)
Because of the electropositive character of the tin atom compared with that of carbon atom, the tin-carbon bond exhibits its reactivity as a carbanion. Since the unprovoked tin-carbon bond is so stable, however, no obvious interference with reactive functional groups is expected during the reaction with other substrates, thus allowing us to prepare tin-containing compounds having various functionalities within the same molecule. Upon manipulating the tin-carbon bond in the second-stage reaction, we can reallize novel types reactions typical of the tin-compounds, which are applicable for the synthetic purpose.
The reagent depicted by I and II can be viewed as double anion (III) or anion/cation (IV) equivalents. We have developed new tin-containing reagents 1-4 as useful synthetic reagents. The reaction types of the tin compounds thus prepared are dependent upon (1) the nature of the functional groups within the same molecule, (2)the method of the activation of the functional groups, (3)relative distance between tin-carbon bond and the functional groups, and (4)the presence of the auxiliary groups. Utilizing these characteristics, we developed novel types reactions (6)-(8), and applied these reactions for the synthesis of some natural products.