MARC보기
LDR00000nam u2200205 4500
001000000431559
00520200224102709
008200131s2019 ||||||||||||||||| ||eng d
020 ▼a 9781687937117
035 ▼a (MiAaPQ)AAI22583027
040 ▼a MiAaPQ ▼c MiAaPQ ▼d 247004
0820 ▼a 574
1001 ▼a Rauch, Martin Paul.
24510 ▼a Development and Applications of Photon Upconversion in Organic Synthesis.
260 ▼a [S.l.]: ▼b Princeton University., ▼c 2019.
260 1 ▼a Ann Arbor: ▼b ProQuest Dissertations & Theses, ▼c 2019.
300 ▼a 207 p.
500 ▼a Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
500 ▼a Advisor: Knowles, Robert R.
5021 ▼a Thesis (Ph.D.)--Princeton University, 2019.
506 ▼a This item must not be sold to any third party vendors.
506 ▼a This item must not be added to any third party search indexes.
520 ▼a Triplet-triplet annihilation photon upconversion (TTA-UC) is a photophysical process in which the energy of two photons are combined into a single photon of higher energy. While this strategy has been implemented in applications ranging from bioimaging to solar energy conversion, its uses in synthetic organic chemistry have not been extensively developed. Here we report the application TTA-UC to produce singlet-state photoexcited intermediates that would otherwise require ultraviolet excitation. In this system, a visible light photosensitizer and a known TTA acceptor work cooperatively to harvest two visible photons and combine their excitations to generate a photon of near UV light in situ. We demonstrate that coumarins can collect this upconverted energy to furnish high-energy singlet excited-state intermediates that can participate in subsequent [2+2] cycloaddition events. We disclose mechanistic and spectroscopic evidence to support both the proposed TTA mechanism for photon upconversion and the singlet energy transfer step to access the excited-state reactivity of coumarins. These findings establish a proof-of-concept for the applicability of TTA-UC systems to mediate a classical UV photochemical transformation using low-energy visible light inputs. We further improve upon this method to newly characterized TTA-UC system that enable access to the excited-state of alpha-keto esters and their subsequent [2+2] cycloadditions.Finally, a method and subsequent mechanistic study for the intramolecular arene alkylation with N-(acyloxy)phthalimides is presented. Spectroscopic, electrochemical, and computational details are provided in support of a closed-cycle catalytic process.
590 ▼a School code: 0181.
650 4 ▼a Organic chemistry.
650 4 ▼a Biochemistry.
690 ▼a 0490
690 ▼a 0487
71020 ▼a Princeton University. ▼b Chemistry.
7730 ▼t Dissertations Abstracts International ▼g 81-05B.
773 ▼t Dissertation Abstract International
790 ▼a 0181
791 ▼a Ph.D.
792 ▼a 2019
793 ▼a English
85640 ▼u http://www.riss.kr/pdu/ddodLink.do?id=T15492750 ▼n KERIS ▼z 이 자료의 원문은 한국교육학술정보원에서 제공합니다.
980 ▼a 202002 ▼f 2020
990 ▼a ***1008102
991 ▼a E-BOOK