Tripodal triphos {MeC(CH2PPh2)(3)} complexes of molybdenum(II) and tungsten(II). Reactions of [MI2(CO)(3){MeC(CH2PPh2)(3)-P,P '}] (M = Mo or W) with molybdenum(II) and tungsten(II) complexes

摘要

Equimolar quantities of [MI2(CO)(3)(NCMe)(2)] (M = Mo or W) and tripodal triphos {MeC(CH2PPh2)(3)} react in CH2Cl2 at room temperature for 5 min to give [MI2(CO)(3){MeC(CH2PPh2)(3)-P,P'}] (1 and 2) which contain one uncomplexed phosphorus donor atom capable of further coordination. Complexes 1 and 2 react in refluxing CHCl3 for 15 h (M = Mo) or 72 h (M = W) to give the complexes [MI2(CO)(2){MeC(CH2PPh2)(3)-P,P',P"}] (3 and 4). The complexes [MI2(CO)(3)(NCMe)(2)] (M = Mo or W) react with two equivalents of 1 (L-Mo) and 2 (L-W) to yield the trimetallic complexes [MI2(CO)(3)(L-Mo or L-W).] (5-8). A series of mixed-ligand seven-coordinate bimetallic complexes of the type [MI2(CO)(3)L(L-Mo or L-W)] {M = Mo or W: L = PPh3. AsPh3, SbPh3; for M = W. P(OR)(3) (R = Me. Et, Ph)} (9-17) have been prepared by reaction of [MI2(CO)(3)(NCMe)(2)] with one equivalent of L to give [MI2(CO)(3)(NCMe)L], followed by an in situ reaction with L-Mo or L-W. Similarly, reactions of [MI2(CO)3{Ph2P(CH2)(n)PPh2}] in = 1 or 21 (prepared in situ) with equimolar amounts of L-Mo or L-W affords the cationic complexes, [MI2(CO)(3){L-Mo or L-W){Ph2P(CH2)(n)PPh2}]I (18-21). Reaction of equimolar quantities of [MI2(CO)(NCMe)(eta(2)-EtC2Et)(2)] and L-Mo (for M = Mo) or L-W (for M = W) affords the acetonitrile displaced products. [MI2(CO)(L-Mo or L-W)(eta(2)-EtC2Et)(2)] (22) and (23). Treatment of [MI2(CO)(NCMe)(eta(2)-EtC2Et)(2)] with two equivalents of L-Mo (for M = Mo) or L-W (for M = W) gives the mono(3-hexyne) trimetallic complexes [MI2(CO)(L-Mo or L-W)(2)(eta(2) -EtC2Et)] (24) and (25). All the new complexes described in this paper have been characterised by elemental analysis, IR, H-1- and P-31-NMR spectroscopy. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 39]