Darstellung und Eigenschaften von und Reaktionen mit metallhaltigen Heterocyclen, LXXVI Regioselektive Cyclocotrimerisierung einer Thiophosphinit‐Einheit mit Methylpropinoat

Metal‐Containing Heterocycles: Preparation, Properties, Reactions, LXXVI. – Regioselective Cyclocotrimerization of a Thiophosphinito Unit with Methyl Propynoate The P = S function of (η 2 ‐PCy 2 =S)Mn(CO) 4 ( 1 ) undergoes a regiospecific cyclocotrimerization with methyl propynoate to give the bicyclic compound 3 . Oxidation of 3 with (NH 4 ) 2 [Ce(NO 3 ) 6 ] results in the formation of the thiophene 4 . Compound 3 was characterized on the basis of MS, IR, 31 P{ 1 H}‐, 1 H‐, 13 C{ 1 H}‐NMR spectra and with a 2D‐H,C‐COSY experiment.