zinc dichromate(VI) T=20°C;

silica-supported prop-1-ylsulfonic acid in methanol

1: ammonium thiocyanate With PPh3.Br2 in acetonitrile T=20°C; 2: 2-(1-phenyl-propoxy)-tetrahydro-pyran in acetonitrile T=20°C; Title compound not separated from byproducts;

triphenylphosphine; 2,3-dicyano-5,6-dichloro-p-benzoquinone in acetonitrile 20 h; Heating;