Bulky alky diphosphines of the type - have been at the heart of many key developments in transition metal chemistry over the last 25 years1-7 including the stabilisation of unusual oxidaton states and low coordination numbers,1-2 formation of agostic alkyls,polyhydride complexes. 1,3,5 Recently bulky alkyl diphosphine complexes of palladium have attraction.7 We report here a simple route to a new class of very bulky alkyl diphosphines which are air-stable