A new route to achiral and chiral 1,2-bis(phosphino)ethanes, 1-arsino-2-phosphinoethanes, and 1,3-bis(phosphino)propanes and the molecular structure and catalytic activity of some rhodium(i) complexes derived thereof Dedicated to Professor Wolfdieter A. Schenk, a respected colleague and creative scientist, on the occasion of his 60th birthday.