1: 1-bromo-2-methyl-1-propene With iodine; magnesium in tetrahydrofuran 0.05 h; Heating / reflux; 2: With methyl iodide in tetrahydrofuran T=25°C; 2.5 h; Heating / reflux; 3: tributyltin chloride in tetrahydrofuran 19 h; Heating / reflux;

sodium hydrogen sulphate; sulfuric acid; water in pyridine; dichloromethane byproducts: p-H3CC6H4OH; slow addn. of soln. of CH3PhOC(S)Cl in CH2Cl2 to cold (-20°C) soln. of alcohol in pyridine, 3h. 0°C, ice, extd. with CH2Cl2, treatment with H2SO4 (10percent), NaHCO3 (10percent), H2O; mixt. warmed up to 200°C, then thermolysis at 850°C; in N2, condensation of products in a dewar vessel (liquid N2), warmed up to ambient temp.; first reaction detected by HPLC and IR, purifn. of educt by chromy. (Florisil, pentane), purifn. checked by HPLC or GC;

in tetrahydrofuran addn. of vinyl bromide and ethylene dibromide to Mg in THF (N2 atmosphere), addn. of further vinyl bromide in THF during 1 h at reflux, decantation, addn. of Sn-compd., refluxing (1 h), cooling room temp.); evapn., partition (Et2O-H2O), washing etheral phase (H2O), drying, evapn., distn.; elem. anal.;

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 in N2, condensation of; products in a dewar vessel (liquid N2), warmed up to ambient temp.; first reaction detected IR and NMR, purifn. of intermediate (acetate) by chromy. (Florisil, pentane);

in chloroform byproducts: cyclohexene; room temp., 2 min; not isolated; (1)H-NMR monitoring;

boron trifluoride diethyl etherate; triphenylbismuth(V) difluoride 1.) CH2Cl2, reflux, 25 h, 2.) DMF, -50 deg C to r.t., 12 h; Yield given. Multistep reaction. Yields of byproduct given;

boron trifluoride diethyl etherate; triphenylbismuth(V) difluoride 1.) CH2Cl2, r.t., 12 h, 2.) DMF, H2O, r.t., 12 h; Yield given. Multistep reaction. Yields of byproduct given;

in chloroform byproducts: cyclohexene; room temp., 2 min; not isolated; (1)H-NMR monitoring;

in benzene Irradiation (UV/VIS); mixt. of substrate and mercurial is irradiated in nitrogen-purged solvent in Pyrex tube with 275-W sunlamp for 18 h; mixt. is poured into water, extd., extract is washed twice with aq. sodium thiosulfate, dried over anhyd. Na2SO4, concd.; (1)H-NMR;

boron trifluoride diethyl etherate; triphenylbismuth(V) difluoride 1.) CH2Cl2, reflux, 25 h, 2.) DMF, -50 deg C to r.t., 12 h; Yield given. Multistep reaction. Yields of byproduct given;