A Novel Ferrocene‐Backboned Unsymmetrical Pincer‐Type Proligand and Its Organotin Derivatives

In this contribution we report the synthesis of the novel unsymmetrical ferrocene‐based pincer‐type proligand η 5 ‐CpFeη 5 ‐C 5 H 2 ‐1‐Br‐2‐PPh 2 ‐5‐CH 2 NMe 2 ( 1 ). Its reactivity is demonstrated by isolation of related organotin derivatives η 5 ‐CpFeη 5 ‐C 5 H 2 ‐1‐SnR 3 ‐2‐PPh 2 ‐5‐CH 2 NMe 2 ( 3 , R = Ph; 4 , R = Me). The reactions of compounds 3 and 4 with H 2 O 2 and elemental sulfur gave the corresponding ferrocenylphosphane oxide ( 5 ) and the sulfides ( 6 , 7 ), respectively. Most remarkably, an unprecedented reaction of the organotin derivative 3 with elemental iodine was observed, providing the ammonium salt [η 5 ‐CpFeη 5 ‐C 5 H 2 ‐1‐SnPh 2 I‐2‐P(O)Ph 2 ‐5‐CH 2 NHMe 2 ]I ( 8 ). The compounds are characterized by elemental analyses, 1 H, 13 C, 31 P, 119 Sn NMR spectroscopy, electrospray ionization mass spectrometry, and single‐crystal X‐ray diffraction analyses ( 3–8 ). Also reported are the solid‐state structures of the hydrolysis products [η 5 ‐CpFeη 5 ‐C 5 H 2 ‐1‐SnPh 2 (OH)‐2‐P(O)Ph 2 ‐5‐CH 2 NHMe 2 ] · 0.5H 2 O ( 9a ) and [η 5 ‐CpFeη 5 ‐C 5 H 2 ‐1‐SnPh(OH)‐2‐P(O)Ph 2 ‐5‐CH 2 NMe 2 ] 2 [I 3 ] 2 ( 9b ) that were isolated by serendipity.