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Reactions of cis-PtCl2(P((CH2)mCH═CH2)3)2 and Grubbs’ first generation catalyst and then hydrogenations afford cis-PtCl2(P((CH2)n)3P) (cis-2; n = 2m + 2 = 12 (b), 14 (c), 16 (d), 18 (e), 20 (f), 22 (g); 6–40%), derived from 3-fold interligand metatheses. The phosphite complexes cis-PtCl2(P(O(CH2)m*CH═CH2)3)2 are similarly converted to cis-PtCl2(P(O(CH2)n*O)3P) (cis-5; n* = 8 (a), 10 (b), 12 (c), 10–20%). The substitution products cis-PtPh2(P((CH2)n)3P) (cis-6c,d) and cis-PtI2(P(O(CH2)10O)3P) are prepared using Ph2Zn and NaI, respectively. Crystal structures of cis-2c,d,f, cis-5a,b, and cis-6c show one methylene bridge that roughly lies in the platinum coordination plane and two that are perpendicular. The thermal behavior of the complexes is examined. When the bridges are sufficiently long, they rapidly exchange via an unusual “triple jump rope” motion over the PtX2 moieties. NMR data establish ΔH⧧, ΔS⧧, and ΔG298K⧧/ΔG393K⧧ values of 7.8 kcal/mol, −27.9 eu, and 16.1/18.8 kcal/mol for cis-2d, and a ΔG393K⧧...

Reactions of Re(CO)5(X) (X = Cl, Br) or [Re2(CO)4(NO)2(μ-Cl)2(Cl)2] and the phosphines P((CH2)mCH═CH2)3 (m = 6, a; 7, b; 8, c) give mer,trans-Re(CO)3(X)(P((CH2)mCH═CH2)3)2 (53–95%) or cis,trans-Re(CO) (NO) (Cl)2(P((CH2)6CH═CH2)3)2 (57%), respectively. Additions of Grubbs’ catalyst (5–10 mol %, 0.0010–0.0012 M) and subsequent hydrogenations (PtO2, ≤5 bar) yield the gyroscope-like complexes mer,trans-Re(CO)3(X)(P((CH2)n)3P) (n = 2m + 2; X = Cl, 7a,c; Br, 8a,c; 18–61%) or cis,trans-Re(CO)(NO)(Cl)2(P((CH2)14)3P) (14%), respectively, and/or the isomers mer,trans-Re(CO)3(X)(P(CH2)n−1CH2)((CH2)n)(P(CH2)n−1CH2) (X = Cl, 7′a–c; Br, 8′b; 6–27%). The latter are derived from a combination of interligand and intraligand metatheses. Reactions of 7a or 8a with NaI, Ph2Zn, or MeLi give mer,trans-Re(CO)3(X)(P((CH2)14)3P) (X = I, 11a; Ph, 12a; Me, 13a; 34–87%). The 13C NMR spectra of 7a–c, 8a–c, 11a, and 13a show rotation of the Re(CO)3(X) moieties to be fast on the NMR time scale at room temperature (and at −90 °C for 8a)...

Reactions of cis-PtCl

Reactions of Br(CH2)mCH=CH2 with Mg powder and then PCl3 (0.33 equiv.) afford P((CH2)m- CH=CH2)3 (1; m = a, 4; b, 5; c, 6; d, 7; e, 8; f, 9; 52 - 87%). Reactions of 1a - c, e with PdX2(COD) (X = Cl, Br) give trans-PdX2(P((CH2)mCH=CH2)3)2 (35 - 92%). Reactions of 1b - e with PtCl2 in benzene give mainly trans-PtCl2(P((CH2)mCH=CH2)3)2 (trans-5b-e; 52 - 75%), whereas those with K2PtCl4 in water give mainly cis-5b-e (33 - 70%). The reaction of equimolar quantities of 1c and H3B・S(CH3)2 gives the 1 : 1 adduct H3B・P((CH2)6CH=CH2)3 (85%). In none of these transformations are by-products derived from the C=C linkages observed

Threefold ring-closing metatheses of mer,trans-Re(CO)3(X)(P((CH2)6CHCH2)3)2 (X = Cl, Br), followed by hydrogenations, yield the gyroscope-like species which react with NaI or Ph2Zn to give substitution products; crystal structures have been determined, and low-temperature NMR data indicate rapid rotation of the Re(CO)3(X) moieties.