Thermally reversible photoisomerization of a square-planar trans-diphosphinedichloropalladium(II) complex to yield its elusive cis-isomer

Abstract

U.v. irradiation of trans-bis(tri-n-propylphosphine)dichloropalladium(II) in solution yields a photostationary trans–cis mixture which reverts quantitatively to the trans-form in the dark with an exceptionally high activation energy; the hitherto elusive cis-form has been characterised by u.v., i.r., and ³¹P n.m.r. spectroscopy and is relatively stable in solution (t_½ 10³ h) at 273 K.