|Budget Amount *help
¥2,600,000 (Direct Cost : ¥2,600,000)
Fiscal Year 1999 : ¥800,000 (Direct Cost : ¥800,000)
Fiscal Year 1998 : ¥1,800,000 (Direct Cost : ¥1,800,000)
The reactions of the vinamidinium salts having 3 kinds of fluoro substituents at β carbon with 1, n-alkanediamines were investigated. The reaction β-fluoro- [I] and β-trifluoroethoxy vinamidinium salt [II] with ethylenediamine gave the corresponding fluorinated 7-membered ring compounds, diazepinium salts, in good yields. On the contrary, β-trifluoromethyl vinamidinium salt [III] reacted easily with ethylenediamine to afford a mixture of trifluoromethylated 14- and 21-membered ring compounds without giving of 7-membered ring compound. The ratio of both products was about 1:1 and selective formation of 14-membered ring compound was observed when large amounts of ethylenediamine was employed and the reaction was conducted in high dilute solution. The structures of these large membered ring compounds were determined by various spectra data, especially HRMS, and finally confirmed by X-ray structural analysis. However, interestingly, N-methyl- and N, N'-dimethylethlenediamine reacted with III to give only the corresponding 7-membered ring compounds in good yields. The reason why the reaction of vinamidinium salt III with ethylenediamine did not produce the 7-membered ring compound was considered by aid of MO calculations. The mechanism of the formation of large membered ring compound was discussed.
The reactions of III with other 1, n-alkanediamine such as 1, 3-propanediamine, 1, 4-butanediamine and 1, 6-hexanediamine were also studied. In all cases, mixtures of the large membered ring compounds, which both substrates reacted in ratio of 2:2 and 3:3, were obtained in good yields.
In summary, the reaction of vinamidinium salt III with 1, n-alkanediamine smoothly proceeded to produce trifluoromethylated large membered ring compounds of different ring size. This reaction could be a new useful method to synthesize large membered ring polyamines.