Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1998.
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| Format: | Thesis |
| Language: | eng |
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Massachusetts Institute of Technology
2005
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| Online Access: | http://hdl.handle.net/1721.1/9636 |
| _version_ | 1826216096707903488 |
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| author | Troutman, Malisa V. (Malisa Vaughn), 1970- |
| author2 | Stephen L. Buchwald. |
| author_facet | Stephen L. Buchwald. Troutman, Malisa V. (Malisa Vaughn), 1970- |
| author_sort | Troutman, Malisa V. (Malisa Vaughn), 1970- |
| collection | MIT |
| description | Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1998. |
| first_indexed | 2024-09-23T16:42:15Z |
| format | Thesis |
| id | mit-1721.1/9636 |
| institution | Massachusetts Institute of Technology |
| language | eng |
| last_indexed | 2024-09-23T16:42:15Z |
| publishDate | 2005 |
| publisher | Massachusetts Institute of Technology |
| record_format | dspace |
| spelling | mit-1721.1/96362020-07-07T19:44:14Z Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins Troutman, Malisa V. (Malisa Vaughn), 1970- Stephen L. Buchwald. Massachusetts Institute of Technology. Department of Chemistry Chemistry Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1998. Includes bibliographical references (leaves 97-98). A highly reactive chiral catalyst for the asymmetric hydrogenation of aryl trisubstituted olefins was generated by combining the complex (EBTHI)MMe2 (EBTHI = ethylenebistetrahydroindenyl, M = Ti, Zr) with [PhMe2NH]+[(BC6F5)4]- under a hydrogen atmosphere. A number of unfunctionalized trisubstituted olefins could be hydrogenated rapidly at room temperature under 80 psig H2 with a wide range of ee's (7 97% ). Reduction of some substrates under a deuterium atmosphere revealed that olefins which gave low ee's were being isomerized to 1, 1-disubstituted olefins prior to reduction. In some cases, additional deuterium was introduced at nonolefinic carbon atoms, indicating that the metal complexes also catalyze directed C-H activation. The zirconium-based catalyst was also applied to the first highly enantioselective hydrogenations of unfunctionalized tetrasubstituled olefins. Hydrogenations of l ,2- dimethyi-3,4-dihydronaphthalene proceeded with high enantioselectivity, but were accompanied by side reactions. At 80 - 2000 psig H2, hydrogenations of a number of fully substituted unfunctionalized indenes proceeded cleanly to give mostly cis products with ee's of 78 - 99%; rates and enantioselectivities increased with increasing pressure. Again, deuteration experiments showed that isomerization processes may occur under the reaction conditions. by Malisa V. Troutman. Ph.D. 2005-08-19T19:05:58Z 2005-08-19T19:05:58Z 1998 1998 Thesis http://hdl.handle.net/1721.1/9636 42363676 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 99 leaves 6080049 bytes 6079805 bytes application/pdf application/pdf application/pdf Massachusetts Institute of Technology |
| spellingShingle | Chemistry Troutman, Malisa V. (Malisa Vaughn), 1970- Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| title | Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| title_full | Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| title_fullStr | Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| title_full_unstemmed | Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| title_short | Asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| title_sort | asymmetric hydrogenation of unfunctionalized trisubstituted and tetrasubstituted olefins |
| topic | Chemistry |
| url | http://hdl.handle.net/1721.1/9636 |
| work_keys_str_mv | AT troutmanmalisavmalisavaughn1970 asymmetrichydrogenationofunfunctionalizedtrisubstitutedandtetrasubstitutedolefins |