Organmetallic Selenolates, IV. Reactions of MSeW(CO)₃cp (M=Li, Na) with Organodi‐ and ‐tetrahalides – X‐ray Crystal Structures of C₆H₅CH₂W(CO)₃(η⁵‐C₅H ₅), μ‐[m‐C₆H₄{CH₂SeW(CO)₃(η⁵‐C₅H₅)}₂], μ‐[p‐C₆H₄{CH₂SeW(CO)_3‐ (η⁵‐C₅H₅)}₂], and C<

Abstract

Organotungsten-selenolato complexes were prepared in moganomonohalides. Moreover, the X-ray crystal structures derate yields by insertion of selenium into the alkali metal-of C6H5CH2W(C0)3cp (l), ~-[m-C6H4(CH2SeW(CO)~cp]2] tungsten bonds of MSeW(CO),cp (M = Li, Na) and subse-(3), ~L -[~-C , H~( C H~S~W ( C O )~C~}~](4), and C6H5CH[SeWquent reactions with the organohalides 0-, m-, and p-(CO)3cp]2 (5) were deJermined. In complex (l), the W-CH2 C6H4(CH2Br)2, C6H5CHBr2, m-C6H4(CHBr2)2 and C6H5CC1,. bond length is 2.374 A; the W-Se bond lengths in the com-The ??Se-NMR data of the new complexes are discussed and plexes 3, 4 , and 5 are all in the range 2.625-2.655 A, correcompared with those of related complexes derived from orsponding to W-Se single bonds.

Organometallic Selenolates. 5.1 Synthesis and Complexing Properties of 2-Propene- and 2-Methyl-2-propeneselenolato Molybdenum and Tungsten Compounds. Crystal Structures of cp(CO)3WSeCH2C(CH3)CH2, [cp(CO)2MoSeCH2C(CH3)CH2]2, [cp(CO)3Mo(μ-SeCH2C(CH3)CH2)W(CO)5], [cp(CO)3Mo(μ-SeCH2C(CH3)CH2)Mo(CO)5<

“…10, 1997 showed several other inseparable species in the reaction mixtures, suggesting a more complicated mechanism. 1 H-and 77 Se-NMR data for the new complexes are in accordance with their formulation. For 1, 2, 4, and 8, the 1 H-1 H coupling pattern for the allylic sites is well resolved and shows typical 3 J H-H and 4 J H-H coupling constants.…”

“…LiSeMo(CO)3cp solutions in 40 mL of THF were prepared from [cpMo(CO) 3]2 (1 g, 2.04 mmol), 1 m LiBEt3H solution in THF (4.1 mL, 4.1 mmol), and gray selenium (0.315 g, 4.08 mmol) according to the published method. 8a The deep red-brown reaction mixtures were treated with an excess of allyl chloride (0.5 mL, 6.1 mmol) (1) or β-methallyl chloride (0.5 mL, 5.1 mmol) (2) via a syringe. The color changed to deep red immediately.…”

“…1 H-NMR: δ 3.06(d, 2H, 4.44 (s, 5H, C5H5), 4.97 (d, 1H, cis H 2CdCH,3 JH-H 9.9 Hz),5.11 (d, 1H, trans H2CdCH,3 JH-H 16.7 Hz), 5.67 (ddt, 1H, dCH-).13 C-NMR: δ 34.26 (-CH2-), 93.77 (C 5H5), 119.05 (dCH2), 136.18 (dCH-), 206.26, 212.24, 217.29, 225.41, 234.30 (CO).…”