Theoretical Studies on the Photoinduced Rearrangement Mechanism of a-Santonin

CORC > 厦门大学 > 化学化工－已发表论文

	Theoretical Studies on the Photoinduced Rearrangement Mechanism of a-Santonin
	Chen, Xing ; Rinkevicius, Zilvinas ; Luo, Yi ; Agren, Hans ; Cao, Zexing ; Cao ZX(曹泽星)
刊名	http://dx.doi.org/10.1002/cphc.201100451
	2012-01-16
关键词	DENSITY-FUNCTIONAL THEORY 2ND-ORDER PERTURBATION-THEORY CORRELATED WAVE-FUNCTIONS PHOTOSANTONIC ACID ORGANIC-PHOTOCHEMISTRY EXCITATION-ENERGIES ALPHA-SANTONIN BASIS-SETS APPROXIMATION MOLECULES
英文摘要	National Science Foundation of China [20733002, 20873105]; Ministry of Science and Technology [2011CB808504]; Swedish Infrastructure Committee (SNIC) [SNIC 014/10-30]; a-Santonin is the first organic compound observed to feature a photoinduced rearrangement and is now known to undergo a series of photochemical processes under UV irradiation. On the basis of the considerable interest of this system as a prototype, and of the yet limited insights reached for the basic photo mechanisms, we calculate the high-level electronic structures and explore the potential energy surfaces (PES) of a-santonin in the ground and lowest-lying excited states, their couplings, and the possible photoinduced isomerization pathways. The calculations identify the low-lying singlet excited state 1(np) accessible under light irradiation, which decays to the low-energy 3(pp) state through an intersystem crossing in the FranckCondon region to initiate the photoinduced rearrangement. The initial reaction from the C3?C5 bond coupling, which takes place on the 3(pp*) state potential energy surface, leads to a three-membered alkyl-ring compound intermediate state INT. The following photochemical reactions have the possibility to arise from two distinct C?C bond cleavages, C4?C5 and C3?C4, denoted as path A and path B. Path A is favored both dynamically on the excited-state PES and thermodynamically on the ground-state PES in vacuo. Experiments show that it also becomes the dominant photoinduced rearrangement process in the crystal, which can be explained by considering the requirement for less space and the stacking effect under the confined environment. Path B is dynamical advantaged both on the ground- and excited-state PESs in a weak polar solvent, such as dioxane. Once the biradical intermediate B-INT is accessible on the ground-state PES, the formation of the product B-P is almost barrier free.
语种	英语
内容类型	期刊论文
源URL	[http://dspace.xmu.edu.cn/handle/2288/62080]
专题	化学化工－已发表论文
推荐引用方式 GB/T 7714	Chen, Xing,Rinkevicius, Zilvinas,Luo, Yi,et al. Theoretical Studies on the Photoinduced Rearrangement Mechanism of a-Santonin[J]. http://dx.doi.org/10.1002/cphc.201100451,2012.
APA	Chen, Xing,Rinkevicius, Zilvinas,Luo, Yi,Agren, Hans,Cao, Zexing,&曹泽星.(2012).Theoretical Studies on the Photoinduced Rearrangement Mechanism of a-Santonin.http://dx.doi.org/10.1002/cphc.201100451.
MLA	Chen, Xing,et al."Theoretical Studies on the Photoinduced Rearrangement Mechanism of a-Santonin".http://dx.doi.org/10.1002/cphc.201100451 (2012).