Mononuclear and Heterodinuclear Metal Complexes of Nonsymmetric Ditertiary Phosphanes Derived from R₂PCH₂OH

<jats:title>Abstract</jats:title><jats:p>The new nonsymmetric ditertiary phosphanes, Ph<jats:sub>2</jats:sub>PCH<jats:sub>2</jats:sub>N(R)CH<jats:sub>2</jats:sub>PAd [<jats:bold>3a</jats:bold>: R = C<jats:sub>6</jats:sub>H<jats:sub>5</jats:sub>, <jats:bold>3b</jats:bold>: R = C<jats:sub>6</jats:sub>H<jats:sub>4</jats:sub>(4‐CH<jats:sub>3</jats:sub>)] were prepared using a three‐step sequence of condensation reactions. Hence treatment of AdP‐H (AdP‐H = 1,3,5,7‐tetramethyl‐2,4,8‐trioxa‐6‐phosphaadamantane) with (CH<jats:sub>2</jats:sub>O)<jats:italic><jats:sub>n</jats:sub></jats:italic> at 110 °C gave the adamantane‐derived hydroxymethylphosphane <jats:bold>1</jats:bold>, which upon condensation with C<jats:sub>6</jats:sub>H<jats:sub>5</jats:sub>NH<jats:sub>2</jats:sub> or C<jats:sub>6</jats:sub>H<jats:sub>4</jats:sub>(4‐CH<jats:sub>3</jats:sub>)NH<jats:sub>2</jats:sub> gave the secondary aminophosphanes HN(R)CH<jats:sub>2</jats:sub>PAd [<jats:bold>2a</jats:bold>: R = C<jats:sub>6</jats:sub>H<jats:sub>5</jats:sub>, <jats:bold>2b</jats:bold>: R = C<jats:sub>6</jats:sub>H<jats:sub>4</jats:sub>(4‐CH<jats:sub>3</jats:sub>)]. Further condensation of <jats:bold>2a</jats:bold> or <jats:bold>2b</jats:bold> with Ph<jats:sub>2</jats:sub>PCH<jats:sub>2</jats:sub>OH gave <jats:bold>3a</jats:bold> or <jats:bold>3b</jats:bold> in high yields (ca. 85 %) containing the sterically encumbered adamantane cage. The coordination capabilities of <jats:bold>2a</jats:bold>, <jats:bold>3a</jats:bold> and <jats:bold>3b</jats:bold> have been explored with various Pd<jats:sup>II</jats:sup>, Pt<jats:sup>II</jats:sup>, Ru<jats:sup>II</jats:sup>, Ir<jats:sup>III</jats:sup> and Au<jats:sup>I</jats:sup> metal centres. Bridge cleavage of {Pd(κ<jats:sup>2</jats:sup>‐<jats:italic>C</jats:italic>,<jats:italic>N</jats:italic>‐C<jats:sub>16</jats:sub>H<jats:sub>16</jats:sub>N)Br}<jats:sub>2</jats:sub> with 2 equiv. of <jats:bold>2a</jats:bold> gave the neutral, mononuclear complex Pd(κ<jats:sup>2</jats:sup>‐<jats:italic>C</jats:italic>,<jats:italic>N</jats:italic>‐C<jats:sub>16</jats:sub>H<jats:sub>16</jats:sub>N)Br(<jats:bold>2a</jats:bold>) (<jats:bold>4</jats:bold>). Reaction of <jats:bold>3a</jats:bold>/<jats:bold>3b</jats:bold> with MCl<jats:sub>2</jats:sub>(cod) (M = Pt, Pd) gave the corresponding κ<jats:sup>2</jats:sup>‐<jats:italic>P</jats:italic>,<jats:italic>P′</jats:italic>‐chelate complexes <jats:italic>cis</jats:italic>‐MCl<jats:sub>2</jats:sub>(<jats:bold>3</jats:bold>) [<jats:bold>5a</jats:bold>: M = Pt, R = C<jats:sub>6</jats:sub>H<jats:sub>5</jats:sub>, <jats:bold>5b</jats:bold>: Pt, R = C<jats:sub>6</jats:sub>H<jats:sub>4</jats:sub>(4‐CH<jats:sub>3</jats:sub>), <jats:bold>5c</jats:bold>: Pd, R = C<jats:sub>6</jats:sub>H<jats:sub>5</jats:sub>, <jats:bold>5d</jats:bold>: Pd, R = C<jats:sub>6</jats:sub>H<jats:sub>4</jats:sub>(4‐CH<jats:sub>3</jats:sub>)]. In contrast, bridge cleavage of the dimers {RuCl<jats:sub>2</jats:sub>(η<jats:sup>6</jats:sup>‐<jats:italic>p</jats:italic>‐cym)}<jats:sub>2</jats:sub> or {IrCl<jats:sub>2</jats:sub>(η<jats:sup>5</jats:sup>‐Cp*)}<jats:sub>2</jats:sub> with <jats:bold>3a</jats:bold> gave the κ<jats:sup>1</jats:sup>‐<jats:italic>P</jats:italic>‐monodentate complexes RuCl<jats:sub>2</jats:sub>(η<jats:sup>6</jats:sup>‐<jats:italic>p</jats:italic>‐cym)(<jats:bold>3a</jats:bold>) (<jats:bold>6</jats:bold>) and IrCl<jats:sub>2</jats:sub>(η<jats:sup>5</jats:sup>‐Cp*)(<jats:bold>3a</jats:bold>) (<jats:bold>7</jats:bold>), respectively, in which the –PAd group is noncoordinating. Reaction of <jats:bold>6</jats:bold> or <jats:bold>7</jats:bold> with AuCl(tht) (tht = tetrahydrothiophene) gave the mixed‐metal complexes κ<jats:sup>2</jats:sup>‐<jats:italic>P</jats:italic>,<jats:italic>P′</jats:italic>‐μ‐RuCl<jats:sub>2</jats:sub>(η<jats:sup>6</jats:sup>‐<jats:italic>p</jats:italic>‐cym){Ph<jats:sub>2</jats:sub>PCH<jats:sub>2</jats:sub>N(Ph)CH<jats:sub>2</jats:sub>PAd(AuCl)} (<jats:bold>8</jats:bold>) and κ<jats:sup>2</jats:sup>‐<jats:italic>P</jats:italic>,<jats:italic>P′</jats:italic>‐μ‐IrCl<jats:sub>2</jats:sub>(η<jats:sup>5</jats:sup>‐Cp*){Ph<jats:sub>2</jats:sub>PCH<jats:sub>2</jats:sub>N(Ph)CH<jats:sub>2</jats:sub>PAd(AuCl)} (<jats:bold>9</jats:bold>). All new compounds have been fully characterised by spectroscopic and analytical methods. Furthermore, the structures of <jats:bold>2a</jats:bold>, <jats:bold>4</jats:bold>, <jats:bold>5a</jats:bold>, <jats:bold>5b</jats:bold> and <jats:bold>6</jats:bold>–<jats:bold>9</jats:bold> have been elucidated by single‐crystal X‐ray crystallography. The X‐ray structures of <jats:bold>5a</jats:bold>, <jats:bold>5b</jats:bold> and <jats:bold>6</jats:bold>–<jats:bold>9</jats:bold> represent the first examples of crystallographically characterised nonsymmetric ditertiary phosphane complexes bearing one adamantane moiety. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)</jats:p>