Acyl, carbene, vinyl, and azavinylidene ligands in tungsten(II) hydridotris(3,5-dimethylpyrazolyl)borate alkyne complexes

Journal Article · Tue Jun 01 00:00:00 EDT 1993 · Organometallics; (United States)

DOI:https://doi.org/10.1021/om00030a025· OSTI ID:6235327

Feng, S G; White, P S; Templeton, J L ^[1]

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1. Univ. of North Carolina, Chapel Hill (United States)

Reaction of [Tp'(CO)[sub 2]W(PhC[sub 2]Me)][BF[sub 4]] with LiCuR[sub 2] (R = Ph, Me) generates neutral [eta][sup 1]-acyl complexes Tp'(CO)(PhC[sub 2]Me)W([eta][sup 1]-C(O)R) in which the alkyne ligand remains as a four-electron donor. Deprotonation of the alkyne methyl in Tp'(CO)PhC[sub 2]MeW([eta][sup 1]-C(O)Me) produces a nucleophilic propargyl synthon which reacts with MeI to yield an ethyl alkyne complex. Protonation or methylation of the neutral [eta][sup 1]-acyl complexes at the acyl oxygen results in the formation of Fischer-type hydroxy- or methoxycarbene cations, [Tp'(CO)(PhC[sub 2]Me)W=C(OE)R][sup +] (E = H, Me; R = Me, Ph, n-C[sub 4]H[sub 9]). Crystals of the methoxybutylcarbene complex belong to the orthorhombic space group P2[sub 1]2[sub 1]2[sub 1], Z = 4, with unit cell dimensions of a = 15.090(6), b = 16.562(4), and c = 14.624(4) A. Refinement of 273 variables over 2187 reflections led to an R value of 6.4% with R[sub w] = 6.7%. The alkyne ligand aligns itself parallel to the cis metal-carbonyl axis and perpendicular to the plane of the carbene ligand. Reaction of [Tp'(PhC[sub 2]Me)W=C(OMe)Me]CF[sub 3]SO[sub 3] with NaOH in MeOH generates a neutral [sigma]-vinyl complex, Tp'(CO)(PhC[sub 2]Me)W([eta][sup 1]-C(OMe)=CH[sub 2]), via deprotonation of the carbene methyl group. Reaction of [Tp'(CO)(PhC[sub 2]Me)W=C(OMe)Ph][CF[sub 3]SO[sub 3]] with 2 equiv of KCN in MeOH yields a neutral azavinylidene complex, Tp'(CO)(PhC[sub 2]Me)WN=C(CN)CH(OMe)Ph, in which the lone pair of electrons on the nitrogen of the azavinylidene ligand competes with the alkyne [pi] donor orbital for donation to the lone vacant metal d[pi] orbital. 35 refs., 2 figs., 3 tabs.

• OSTI ID: 6235327
• Journal Information: Organometallics; (United States), Journal Name: Organometallics; (United States) Vol. 12:6; ISSN ORGND7; ISSN 0276-7333
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400102 -- Chemical & Spectral Procedures
400201* -- Chemical & Physicochemical Properties
CHEMICAL REACTIONS
COHERENT SCATTERING
COMPLEXES
CRYSTAL STRUCTURE
DATA
DIFFRACTION
ELECTRONIC STRUCTURE
EXPERIMENTAL DATA
INFORMATION
LIGANDS
MAGNETIC RESONANCE
METHYLATION
NUCLEAR MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
RESONANCE
SCATTERING
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
TUNGSTEN COMPLEXES
X-RAY DIFFRACTION