New and convenient synthesis of (R)-(+)-4, 5-Dihydro-4-methyl-2(3H)-furanone and (R)-(-)-4-Bromo-3-methyl-1-O-tert-butyldimethyl-silylbutan-1-ol

A convenient partial synthesis of the lactone (+)- 10 is reported starting from the readily available methyl (S)-(+)-3-hydroxy-2-methylpropanoate (+)- 1 . Furthermore, an efficient three step route to the optically active saturated isoprene unit (-)- 13 in high yield starting from the lactone (+)- 10 is reported for the first time.