sodium hydride in isopropyl alcohol; benzene (Ar); excess of NaH and dry isopropanol stirred for ca. 0.5 h, soln. of semicarbazone in C6H6 added slowly, mixt. refluxed for 2.5 h, mixt. cooled to room temp., soln. of tin-compound in C6H6 added dropwise, mixt. refluxed for 2 h; mixt. filtered, filtrate evapd. (reduced pressure, rotary evaporator), recrystd. from 2:1 mixt. of benzene and petroleum ether at 40-60 °C; elem. anal.;

sodium hydride in isopropyl alcohol; benzene (Ar); excess of NaH and dry isopropanol stirred for ca. 0.5 h, soln. of semicarbazone in C6H6 added slowly, mixt. refluxed for 2.5 h, mixt. cooled to room temp., soln. of tin-compound in C6H6 added dropwise, mixt. refluxed for 2 h; mixt. filtered, filtrate evapd. (reduced pressure, rotary evaporator), recrystd. from 2:1 mixt. of benzene and petroleum ether at 40-60 °C; elem. anal.;

sodium hydride in isopropyl alcohol; benzene (Ar); NaH and dry isopropanol stirred for ca. 0.5 h, soln. of semicarbazone in C6H6 added slowly, mixt. refluxed for 2.5 h, mixt. cooled to roomtemp., soln. of tin-compound in C6H6 added dropwise, mixt. refluxed for 2 h; mixt. filtered, filtrate evapd. (reduced pressure, rotary evaporator), recrystd. from 2:1 mixt. of benzene and petroleum ether at 40-60 °C; elem. anal.;

sodium hydride in isopropyl alcohol; benzene (Ar); NaH and dry isopropanol stirred for ca. 0.5 h, soln. of semicarbazone in C6H6 added slowly, mixt. refluxed for 2.5 h, mixt. cooled to roomtemp., soln. of tin-compound in C6H6 added dropwise, mixt. refluxed for 2 h; mixt. filtered, filtrate evapd. (reduced pressure, rotary evaporator), recrystd. from 2:1 mixt. of benzene and petroleum ether at 40-60 °C; elem. anal.;

sodium hydride in isopropyl alcohol; benzene (Ar); NaH and dry isopropanol stirred for ca. 0.5 h, soln. of semicarbazone in C6H6 added slowly, mixt. refluxed for 2.5 h, mixt. cooled to roomtemp., soln. of tin-compound in C6H6 added dropwise, mixt. refluxed for 2 h; mixt. filtered, filtrate evapd. (reduced pressure, rotary evaporator), recrystd. from 2:1 mixt. of benzene and petroleum ether at 40-60 °C; elem. anal.;