Journal article
Metal-metal multiple bonds. 18. Addition reactions of diazoalkanes with the molybdenum-molybdenum triple bond in R2Mo2(CO)4 (R = C5H5, C5H4Me, C5Me5)
Organometallics, Vol.5(11), pp.2283-2294
11/01/1986
DOI: 10.1021/om00142a018
Abstract
The Mo=Mo triple bond in R2Mo2(CO)4(R = C5H5, C5H4Me, C5Me6) (1) reacts with diazoalkanes to give 1:1 adducts whose bonding modes depend markedly on the substituents, R, as well as on the diazoalkane. Diaryldiazomethanes form an adduct in which the terminal N atom asymmetrically bridges a Mo-Mo single bond. Bond distances suggest the N atom is doubly bonded to one Mo atom and singly bonded to the other. These adducts (R = Cp) lose N2 upon photolysis or thermolysis via an intramolecular 1, 3-dipolar cycloadduct to give μ-diarylmethylene complexes. Me2CN2 reacts to give a mixture of isomers, one similar to the diaryldiazomethane adducts and the other contains a μ-η1, η2-diazoalkane bridge with the terminal nitrogen bonded to both Mo atoms and the central N atom bonded to only one. Ethyl diazoacetate forms an adduct with the latter structure when R = C5Me5. Diethyl diazomalonate or a-keto diazoalkanes react with 1 to give adducts in which the carboxyl or ketone oxygen forms a chelate ring to one Mo atom and the metal-metal bond is broken entirely. 1H and 13C NMR spectra for these complexes are reported. The crystal structures of Cp2Mo2(CO)4(μ-N2CPh2) (2), Cp2Mo2(CO)4[N2C(CO2Et)2] (4A), and (C5Me6)2Mo2-(CO)4(N2CHC02Et) (6) were determined. For 2: a = 11.847 (4) A, b = 10.407 (3) A, c = 20.572 (6) A; β = 97.81 (2)°; V = 2513 (1) A3; Z = 4, p = 1.64 g/mL; space group P21/n (no. 14); R1= 0.048, R2= 0.059. Some pertinent bond distances (A): Mol-Mo2 = 2.987 (4), Mol-Nl = 1.914 (8), Mo2-Nl = 2.083 (8), N1-N2 = 1.35 (1), N2-C15 = 1.28 (1). For 4A: a = 11.144 (2) A, b = 7.497 (1) A, c = 28.939 (7); 0 = 95.13 (2)°; V = 2408.2 (9) A3; Z = 4; ρcalcd= 1.71 g/mL; space group P21/c (no. 14); R1 = 0.048, R2= 0.061. Selected distances (A): Mol-Nl = 1.86 (1), N1-N2 = 1.24 (1), N2-C15 = 1.42 (1), C15-C16 = 1.41 (2), C16-05 = 1.26 (1), 05-Mo2 = 2.14 (1), Mo2-N2 = 2.21 (1). For 6: a = 10.515 (3) A, b- 18.868 (6) A, c = 15.334 (4) A; p = 104.43 (2)°; V = 2946 (1) A3; Z = 4, pcalcd = 1.55 g/mL; space group P21/n (no. 14); Rx = 0.034, R2= 0.035. Selected distances (A): Mol-Mo2 = 3.040 (1), Mol-Nl = 2.105 (4), Mo2-Nl = 2.109 (4), Mo2-N2 = 2.108 (5), N1-N2 = 1.336 (6), N2-C5 = 1.288 (7). © 1986, American Chemical Society. All rights reserved.
Details
- Title: Subtitle
- Metal-metal multiple bonds. 18. Addition reactions of diazoalkanes with the molybdenum-molybdenum triple bond in R2Mo2(CO)4 (R = C5H5, C5H4Me, C5Me5)
- Creators
- M. David CurtisL MesserleJohn J D'ErricoWilliam M ButlerMichael S Hay
- Resource Type
- Journal article
- Publication Details
- Organometallics, Vol.5(11), pp.2283-2294
- Publisher
- American Chemical Society
- DOI
- 10.1021/om00142a018
- ISSN
- 0276-7333
- eISSN
- 1520-6041
- Language
- English
- Date published
- 11/01/1986
- Academic Unit
- Chemistry; Radiology
- Record Identifier
- 9984216666702771
Metrics
3 Record Views