1258512-08-1Relevant articles and documents
TPZ, a bright centrosymmetric two-photon scaffold for bioimaging
Lei, Zuhai,Yue, Ping,Wang, Xueli,Li, Xinran,Li, Yi,He, Haihong,Luo, Xiao,Meng, Xiangming,Chen, Jinquan,Qian, Xuhong,Yang, Youjun
, p. 10938 - 10941 (2017)
The development of biocompatible two-photon fluorophores with a large absorption cross-section is challenging, despite the presence of theoretical guidelines. By rendering asymmetric PRODAN dye centrosymmetric, we designed and synthesized a novel class of two-photon fluorophores (TPZ). Their photophysical properties were investigated and their imaging potentials in cells, tissues and zebrafish were showcased.
Catalytic Synthesis of 8-Membered Ring Compounds via Cobalt(III)-Carbene Radicals
Lankelma, Marianne,Zhou, Minghui,de Bruin, Bas,van der Vlugt, Jarl Ivar
, p. 11073 - 11079 (2020/04/29)
The metalloradical activation of o-aryl aldehydes with tosylhydrazide and a cobalt(II) porphyrin catalyst produces cobalt(III)-carbene radical intermediates, providing a new and powerful strategy for the synthesis of medium-sized ring structures. Herein we make use of the intrinsic radical-type reactivity of cobalt(III)-carbene radical intermediates in the [CoII(TPP)]-catalyzed (TPP=tetraphenylporphyrin) synthesis of two types of 8-membered ring compounds; novel dibenzocyclooctenes and unprecedented monobenzocyclooctadienes. The method was successfully applied to afford a variety of 8-membered ring compounds in good yields and with excellent substituent tolerance. Density functional theory (DFT) calculations and experimental results suggest that the reactions proceed via hydrogen atom transfer from the bis-allylic/benzallylic C?H bond to the carbene radical, followed by two divergent processes for ring-closure to the two different types of 8-membered ring products. While the dibenzocyclooctenes are most likely formed by dissociation of o-quinodimethanes (o-QDMs) which undergo a non-catalyzed 8π-cyclization, DFT calculations suggest that ring-closure to the monobenzocyclooctadienes involves a radical-rebound step in the coordination sphere of cobalt. The latter mechanism implies that unprecedented enantioselective ring-closure reactions to chiral monobenzocyclooctadienes should be possible, as was confirmed for reactions mediated by a chiral cobalt-porphyrin catalyst.
NHC-catalyzed spiro bis-indane formation via domino stetter - Aldol - Michael and stetter - Aldol - Aldol reactions
Sanchez-Larios, Eduardo,Holmes, Janice M.,Daschner, Crystal L.,Gravel, Michel
, p. 5772 - 5775 (2011/03/22)
Two novel domino NHC-catalyzed spirocyclizations are described herein, enabling the rapid construction of three new carbon - carbon bonds and a quaternary center with high diastereoselectivity. A variety of spiro bis-indane structures are assembled in a single step from simple o-phthaldialdehyde derivatives.
