n-butyllithium in tetrahydrofuran; hexane to a stirred soln. of phosphonium-compd. in THF at 0°C is added a soln. of BuLi in hexane under N2, the mixt. is stirred at room temp. for 1 h and recooled to 0°C, addn. of Sn-compd. and the mixt. is stirred for 12 h, addn. of aq. NH4Cl; extraction with light petroleum, the extract is dried (MgSO4) and evaporated under reduced pressure, purifn. by column chromy. on silica gel (elution with pentane);

Burgess Reagent in benzene byproducts: HNEt3(1+)*OSO2NHCO2Me(1-); addn. of alcohol to the inner salt under inert atm., room temp., stirred overnight, heated (70°C, 6 h), hydrolyzed; chromy. (florisil, pentane), entire yields of products 68percent, Bu3Sn(CH3)C=CHCH3 35percent (Z/E ratio 55/45 by (13)C-NMR), E/Z isomers not isolated, Bu3Sn(C2H5)C=CH2 65percent;

in diethyl ether byproducts: magnesium chloride, acetic acid; 1: addn. of soln. of carbonyl in ether to equimolar amts. of Bu3SnMgCl in ether, addn. of CH3COCl, reflux, under inert atmosphere, filtration, distn. in vac.; 2: mixt. warmed up to 200°C, then thermolysis at 650°C in N2, condensation of; products in dewar vessel (liquid N2), warmed up to ambient temp.; first reaction detected IR and NMR, purifn. of intermediate (acetate) and product by chromy. (Florisil, pentane), ratio of Bu3Sn(CH3)C=CHCH3 isomers: Z/E = 54/46 (detected by (13)C-NMR);

methyl iodide in tetrahydrofuran (Ar); Soln. of (Bu)3SnLi in THF added to stirred suspensn. of CuCN in THF at -78 °C, mixt. stirred for 30 min at this temp.; 30 min react. on CO2/acetone bath with allene; MeI soln. added dropwise at -78, 1 h stirring, then 3 h at 0 °C; aqueous workup using Et2O; chromy.; overall yield: 91 percent; ratio 1-(Bu)3Sn-2-heptene/2-(Bu)3Sn-1-heptene = 4.5/1;

in gaseous matrix flash pyrolysis (vac.) with N2 at 650°C; total yield 76percent; Z/E isomer ratio = 54/46;

in gas byproducts: hexabutylditin, Bu3Sn(CH3)CCHCH3; placing starting material in a porcelain cup in the sublimation chamber of a flash vac. thermolysis apparatus, react. at 800-850°C in the main oven and 250-300°C in the sublimation oven (10E-2 mm), oven packed with broken porcelain; vapors quenched on a dewar cold finger, pyrolysis tube cooled to room temp., product washed from the dewar surface (ether), ether evapd. chromy. (florisil); combined yield 42percent, terminal olefin 60percent, internal olefin Z/E 55/45 detd. by 13C-NMR;

methyl iodide React. of starting materials at -100°C.;