Synthesis of molybdenum imido alkylidene complexes and some reactions involving acyclic olefins

The reaction between Mo(C-t-Bu)(dme)Cl{sub 3} (dme = 1,2-dimethoxyethane) and Me{sub 3}SiNHAr (Ar = 2,6-diisopropylphenyl) yields Mo(C-t-Bu)(NHAr)Cl{sub 2}(dme) (1), which upon treatment with a catalytic amount of NEt{sub 3} is transformed into Mo(CH-t-Bu)(NAr)Cl{sub 2}(dme) (2). Complexes of the type Mo(CH-t-Bu)(NAr)(OR){sub 2} (OR = OCMe(CF{sub 3}){sub 2}, OCMe{sub 2}(CF{sub 3}), O-t-Bu, or OAr) have been prepared from 2. Complexes of the type Mo(C-t-Bu)(NHAr)(OR){sub 2} (OR = OCMe(CF{sub 3}){sub 2} or OAr) have been prepared from 1, but they cannot be transformed into Mo(CH-t-Bu)(NAr)(OR){sub 2} complexes. A precursor to imido alkylidene complexes that is related to 2 has been prepared by the sequence MoO{sub 2} {yields} MoO{sub 2}Cl{sub 2} {yields} Mo(NAr){sub 2}Cl{sub 2} {yields} Mo(NAr){sub 2}(CH{sub 2}R{prime}){sub 2} {yields} Mo(CHR{prime})(NAr)(OTf){sub 2}(dme) (R{prime} = t-Bu or CMe{sub 2}Ph; OTf = OSO{sub 2}CF{sub 3}). Mo(CH-t-Bu)(NAr)(OTf){sub 2}(dme) crystallizes in the space group P{anti 1} with a = 17.543 {angstrom}, b = 19.008 {angstrom}, c = 9.711 {angstrom}, {alpha} = 91.91{degree}, {beta} = 99.30{degree}, {gamma} = 87.27{degree}, Z = 4, M{sub r} = 729.60, V = 3,191.1 {angstrom}{sup 3}, {rho}(calcd) = 1.518 g cm{sup {minus}3}.