ca01 only detailed ToC 1..24

134 Science of Synthesis 2.6 Complexes of Cr, Mo, and W without CO Ligands
Scheme 48 Allylidene Complexes from Cyclopropenes [177,178]
E
X3P
Cl W PX3 Cl
PX3 E = O, NC6H3-2,6-iPr2
Ph Ph
benzene
PX3 = PMePh2, PEt2Ph, P(OMe)3
OR 1 = OCMe(CF3)2
E
X3P
Cl W
Cl PX3 Ph LiOR 1 (2 equiv)
Ph
R 1 O
R 1 O
105 106
Dichloro(2,6-diisopropylphenylimido)(3,3-diphenylallylidene)bis(trimethyl phosphite-
P)tungsten (105, E=NC 6H 3-2,6-iPr 2; X = OMe); Typical Procedure: [178]
A soln of 3,3-diphenylcyclopropene (1.84 g, 9.55 mmol) in benzene (30 mL) was added via
cannula to a soln of [WCl 2(=NC 6H 3-2,6-iPr 2){P(OMe) 3} 3] (7.12 g, 8.88 mmol) in benzene
(60 mL), and the mixture was then stirred for 2 h at 808C. The solvent was removed in vacuo,
and the resulting orange oil was left under dynamic vacuum for an additional 12 h.
The product was then dissolved in THF (95 mL), and the resulting orange soln was filtered.
After all but THF (10 mL) had been removed in vacuo, addition of pentane (150 mL) yielded
an orange powder; yield: 5.50 g (72%); 1 H NMR (90 MHz, toluene-d 8, ä): 12.85 (dt, 1H,
J HH = 12.75, J HP = 6.37, H Æ ), 10.23 (dt, 1H, J HH = 12.75, J HP = 2.45, H â ), 3.65 [t, 18H, P(OMe) 3].
E
W
PX 3
Ph
Ph