Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates
Reaction of the titanium imido complexes [Ti(NR)(N2XylNpy)(L)] (N2XylNpy = MeC(2-C5H4N) {CH2N(3,5-C6H 3Me2)}2) with aryl acetylenes afforded the {2+2} cycloaddition products [Ti(N2XylN py){κ2-N(tBu)CH=CAr}] (Ar = Ph: 1a, Tol: 1b (Tol = 4-C6H4Me)). Complex 1a was found to insert sulfur and selenium a...
| Main Authors: | , , , , , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
2008
|
| _version_ | 1826291087479668736 |
|---|---|
| author | Vujkovic, N Fillol, J Ward, B Wadepohl, H Mountford, P Gade, L |
| author_facet | Vujkovic, N Fillol, J Ward, B Wadepohl, H Mountford, P Gade, L |
| author_sort | Vujkovic, N |
| collection | OXFORD |
| description | Reaction of the titanium imido complexes [Ti(NR)(N2XylNpy)(L)] (N2XylNpy = MeC(2-C5H4N) {CH2N(3,5-C6H 3Me2)}2) with aryl acetylenes afforded the {2+2} cycloaddition products [Ti(N2XylN py){κ2-N(tBu)CH=CAr}] (Ar = Ph: 1a, Tol: 1b (Tol = 4-C6H4Me)). Complex 1a was found to insert sulfur and selenium atoms into the Ti-C bond of the strained azatitanacyclobutene unit to give the five-membered metallacyclic systems [Ti(N2XylNpy){κ2-N(tBu)CH= C(Ph)E}] (E = S: 2, Se: 3). Likewise, isonitriles were found to insert into the Ti-C bonds to give [Ti(N2XylNpy) {κ2-N(tBu)CH=C(Ar)C=NR}] (Ar = Ph, R = xylyl: 4, Cy: 5, tBu: 6a; Ar = C6H5Me, R = tBu: 6b), one example of which (4) has been characterized by X-ray crystallography. The latter species is thought to be a key intermediate in the titanium-mediated three-component coupling of primary amines with acetylenes and isonitriles ("iminoamination"). Reaction of [Ti(N2XylN py){κ2-N(tBu)CH=C(Ph)C=NR}] with tBuNH2 gave tBuN=CHC(Ph)CHNHR, which have been previously identified as the major reaction products in the catalytic aminoamination of alkynes. © 2008 American Chemical Society. |
| first_indexed | 2024-03-07T02:54:07Z |
| format | Journal article |
| id | oxford-uuid:aeb2b7a0-66d9-4949-aa2d-d808469a499c |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T02:54:07Z |
| publishDate | 2008 |
| record_format | dspace |
| spelling | oxford-uuid:aeb2b7a0-66d9-4949-aa2d-d808469a499c2022-03-27T03:44:17ZInsertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediatesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:aeb2b7a0-66d9-4949-aa2d-d808469a499cEnglishSymplectic Elements at Oxford2008Vujkovic, NFillol, JWard, BWadepohl, HMountford, PGade, LReaction of the titanium imido complexes [Ti(NR)(N2XylNpy)(L)] (N2XylNpy = MeC(2-C5H4N) {CH2N(3,5-C6H 3Me2)}2) with aryl acetylenes afforded the {2+2} cycloaddition products [Ti(N2XylN py){κ2-N(tBu)CH=CAr}] (Ar = Ph: 1a, Tol: 1b (Tol = 4-C6H4Me)). Complex 1a was found to insert sulfur and selenium atoms into the Ti-C bond of the strained azatitanacyclobutene unit to give the five-membered metallacyclic systems [Ti(N2XylNpy){κ2-N(tBu)CH= C(Ph)E}] (E = S: 2, Se: 3). Likewise, isonitriles were found to insert into the Ti-C bonds to give [Ti(N2XylNpy) {κ2-N(tBu)CH=C(Ar)C=NR}] (Ar = Ph, R = xylyl: 4, Cy: 5, tBu: 6a; Ar = C6H5Me, R = tBu: 6b), one example of which (4) has been characterized by X-ray crystallography. The latter species is thought to be a key intermediate in the titanium-mediated three-component coupling of primary amines with acetylenes and isonitriles ("iminoamination"). Reaction of [Ti(N2XylN py){κ2-N(tBu)CH=C(Ph)C=NR}] with tBuNH2 gave tBuN=CHC(Ph)CHNHR, which have been previously identified as the major reaction products in the catalytic aminoamination of alkynes. © 2008 American Chemical Society. |
| spellingShingle | Vujkovic, N Fillol, J Ward, B Wadepohl, H Mountford, P Gade, L Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates |
| title | Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates |
| title_full | Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates |
| title_fullStr | Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates |
| title_full_unstemmed | Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates |
| title_short | Insertions into azatitanacyclobutenes: New insights into three-component coupling reactions involving imidotitanium intermediates |
| title_sort | insertions into azatitanacyclobutenes new insights into three component coupling reactions involving imidotitanium intermediates |
| work_keys_str_mv | AT vujkovicn insertionsintoazatitanacyclobutenesnewinsightsintothreecomponentcouplingreactionsinvolvingimidotitaniumintermediates AT fillolj insertionsintoazatitanacyclobutenesnewinsightsintothreecomponentcouplingreactionsinvolvingimidotitaniumintermediates AT wardb insertionsintoazatitanacyclobutenesnewinsightsintothreecomponentcouplingreactionsinvolvingimidotitaniumintermediates AT wadepohlh insertionsintoazatitanacyclobutenesnewinsightsintothreecomponentcouplingreactionsinvolvingimidotitaniumintermediates AT mountfordp insertionsintoazatitanacyclobutenesnewinsightsintothreecomponentcouplingreactionsinvolvingimidotitaniumintermediates AT gadel insertionsintoazatitanacyclobutenesnewinsightsintothreecomponentcouplingreactionsinvolvingimidotitaniumintermediates |