Syntheses and structures of edge-sharing bioctahedral dimolybdenum compounds containing carboxylate or formamidinate groups /
This dissertation presents the syntheses and structural
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1996.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=743274351&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | This dissertation presents the syntheses and structural characterizations of eight dinuclear molybdenum compounds: M02C'4(OAC)2(PEt3)2 (1), [PPh4]2[Mo2(OAc)2C'61 (2), Ipph4]2[Mo2(02CPh)2C'61-2CH3CN (3), M02(02CPh)6(pEt3)2- 2CH2C'2 (4), Ipph4l[MO2(]DphF)2Mh)CI5]-2CH2C'2 (6), [PPh4]2[Mo2(DPhF)2C'41-2CH3CN (7), [PPh4][MO2(DPhF)2C'41 (8) and [PPh4][MO2(DPhF)2C'61 (9), and the synthesis and structure of a tetranuclear compound, M0406(02CPh)6(PEt3)2.CH2C'2 (5), which was produced in the synthesis of 4. The syntheses of the carboxylate compounds involve either reactions of M02C'6(TBF)3 with the corresponding carboxylate salts or oxidative additions of the corresponding (Il,ll) species with PhIC'2- Compounds 1-4 have a (IH,HI) oxidation state and edge-sharing bioctahedral (ESBO) structures. The forinamidinate compounds, 6-9, have other oxidation states: (11,II) for 7 (paddle-wheel structure), (II,III) for 8 (paddlewheel structure), (III,IV) for 9 (ESBO structure) and (IV,IV) for 6 (ESBO structure)Compound 6 was synthesized by refluxing M02C'6(TI-IF)3 with HDPHF (N, A7 diphenylformaniidine) in o-dichlorobenzene, 7 and 8 by reactions of M02C'6(TBF)3 with LiDPhF and LiBu, and 9, by oxidative additions of 7 or 8 with PhIC'2- The syntheses of 1-4 have helped to establish a library of closely related compounds for the study on how and to what extent a difference in ligand basicity influences the metal-metal bonding in ESBO compounds. Compounds 6-9 are related to Ipph4]2[Mo2(DphF)2C'61, which was also a primary target for this study. It is found that the M-M distances in ESBO compounds are more sensitive to crystal packing than to a small variation in ligand basicity. The distinctive redox behaviors of the carboxylate and the formamidinate compounds provide an interesting case for how ligand basicity is related to the redox behavior of the complex. |
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| Item Description: | Vita. "Major Subject: Chemistry". |
| Physical Description: | ix, 73 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |