Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes
Reaction of the pseudo two-coordinate titanium imido complexes [Ti(N tBu)(COT)] (1; COT = η8-C8H8) and [Ti(NtBu)(COT″)] (2; COT″ = η 8-1,4-C8H6(SiMe3)2) with 2 equiv of tBuC≡P generated the new complexes [Ti{N( tBu)PC(tBu)PC(tBu)}(COT)] (4) and [Ti{N( tBu)PC(tBu)PC(tBu)}(COT″)] (5), respectively. Co...
| المؤلفون الرئيسيون: | , , , , , , |
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| التنسيق: | Journal article |
| اللغة: | English |
| منشور في: |
2006
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| _version_ | 1826306766401437696 |
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| author | Cloke, F Green, J Hazari, N Hitchcock, P Mountford, P Nixon, J Wilson, D |
| author_facet | Cloke, F Green, J Hazari, N Hitchcock, P Mountford, P Nixon, J Wilson, D |
| author_sort | Cloke, F |
| collection | OXFORD |
| description | Reaction of the pseudo two-coordinate titanium imido complexes [Ti(N tBu)(COT)] (1; COT = η8-C8H8) and [Ti(NtBu)(COT″)] (2; COT″ = η 8-1,4-C8H6(SiMe3)2) with 2 equiv of tBuC≡P generated the new complexes [Ti{N( tBu)PC(tBu)PC(tBu)}(COT)] (4) and [Ti{N( tBu)PC(tBu)PC(tBu)}(COT″)] (5), respectively. Complex 4 was crystallographically characterized, and a density functional theory (DFT) study combined with photoelectron (PE) spectroscopy revealed this apparently 20-valence-electron species to contain a HOMO which is almost entirely ligand-based. In contrast, the organic compound N(Ar)-P 2C2tBu2 (6), which incorporates a 1,2,4-azadiphosphole ring, was the only isolated product from the reaction of the arylimido species [Ti(NAr)(COT)] (3; Ar = 2,6-iPr 2C6H3) with an excess of tBuC≡P. DFT studies indicated that the mechanisms for the formation of compounds 4-6 are similar. Initially, one molecule of tBuC≡P undergoes a [2 + 2] cycloaddition with [Ti(NR)(COT)] to form [Ti{N(R)PC-(tBu)}(COT)], which contains a Ti-C bond. Subsequently, a second molecule of tBuC≡P reacts with [Ti{N(R)PC(tBu)}(COT)] to form [Ti{N(R)PC(tBu)PC( tBu)}(COT)]. When R = 2,6-iPr2C 6H3 or a substituent which is less sterically bulky, the formation of a heterocyclic ring such as N(Ar)P2C2tBu2 (6) is favored. However, when R = tBu, it is sterically unfavorable to form such a ring and thus compound 4 is stable. © 2006 American Chemical Society. |
| first_indexed | 2024-03-07T06:52:53Z |
| format | Journal article |
| id | oxford-uuid:fd217227-c8bc-4e5f-ab04-81059893289e |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T06:52:53Z |
| publishDate | 2006 |
| record_format | dspace |
| spelling | oxford-uuid:fd217227-c8bc-4e5f-ab04-81059893289e2022-03-27T13:26:33ZReactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:fd217227-c8bc-4e5f-ab04-81059893289eEnglishSymplectic Elements at Oxford2006Cloke, FGreen, JHazari, NHitchcock, PMountford, PNixon, JWilson, DReaction of the pseudo two-coordinate titanium imido complexes [Ti(N tBu)(COT)] (1; COT = η8-C8H8) and [Ti(NtBu)(COT″)] (2; COT″ = η 8-1,4-C8H6(SiMe3)2) with 2 equiv of tBuC≡P generated the new complexes [Ti{N( tBu)PC(tBu)PC(tBu)}(COT)] (4) and [Ti{N( tBu)PC(tBu)PC(tBu)}(COT″)] (5), respectively. Complex 4 was crystallographically characterized, and a density functional theory (DFT) study combined with photoelectron (PE) spectroscopy revealed this apparently 20-valence-electron species to contain a HOMO which is almost entirely ligand-based. In contrast, the organic compound N(Ar)-P 2C2tBu2 (6), which incorporates a 1,2,4-azadiphosphole ring, was the only isolated product from the reaction of the arylimido species [Ti(NAr)(COT)] (3; Ar = 2,6-iPr 2C6H3) with an excess of tBuC≡P. DFT studies indicated that the mechanisms for the formation of compounds 4-6 are similar. Initially, one molecule of tBuC≡P undergoes a [2 + 2] cycloaddition with [Ti(NR)(COT)] to form [Ti{N(R)PC-(tBu)}(COT)], which contains a Ti-C bond. Subsequently, a second molecule of tBuC≡P reacts with [Ti{N(R)PC(tBu)}(COT)] to form [Ti{N(R)PC(tBu)PC( tBu)}(COT)]. When R = 2,6-iPr2C 6H3 or a substituent which is less sterically bulky, the formation of a heterocyclic ring such as N(Ar)P2C2tBu2 (6) is favored. However, when R = tBu, it is sterically unfavorable to form such a ring and thus compound 4 is stable. © 2006 American Chemical Society. |
| spellingShingle | Cloke, F Green, J Hazari, N Hitchcock, P Mountford, P Nixon, J Wilson, D Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes |
| title | Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes |
| title_full | Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes |
| title_fullStr | Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes |
| title_full_unstemmed | Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes |
| title_short | Reactions of (BuC)-Bu-t P with cyclooctatetraene-supported titanium imido complexes |
| title_sort | reactions of buc bu t p with cyclooctatetraene supported titanium imido complexes |
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