m 1h 2 73 m 1h 2 39 2 56 cm 3h 1 56 1 63 m 2h 13 c nmr cdcl 3 u03b4197 8 155 4 150 2 130 4 52 2 46 2 41 9 41 4 36 2 33 2 26 2 a mixture of the compound from example 1 2 29 g and 16 palladium on carbon 0 23 g in ethanol 23 ml was hydrogenated using a hydrogen pressure of 20 psi at ambient temperature after 2 hours the catalyst was removed by filtration and the filtrate concentrated in vacuo to give 2 26 g of the title compound as an oil 1 h nmr cdcl 3 u03b43 92 3 99 m 2h 3 67 s 3h 3 11 3 55 m 1h 2 85 2 95 m 1h 2 53 2 60 m 1h 2 12 2 42 m 5h 1 90 2 03 m 2h 1 46 1 52 m 2h 13 c nmr cdcl 3 u03b4209 6 155 4 51 7 46 6 45 2 42 6 39 0 36 3 33 7 26 1 24 6 a mixture of sodium hydride 0 61 g in tetrahydrofuran 15 ml was cooled and treated with tetraethyl methylenediphosphonate 6 36 ml after three hours the reaction mixture was treated with a solution of the compound from preparation 4 2 19 g in tetrahydrofuran 15 ml the resulting mixture was heated to reflux after 21 2 hours the reaction solution was added to water 30 ml and the resulting mixture extracted with ether 3 u00d7 20.