Results 121 to 130 of about 3,272,143 (363)

Organocatalytic C─O Bond Cleavage and Asymmetric Transformations via [1,3]‐Sigmatropic Rearrangement

Advanced Science, EarlyView.
A direct asymmetric strategy for fulfilling the functional group transfer by aryl ether cleavage and migration is developed, representing the first Brønsted base‐catalyzed asymmetric [1,3]‐sigmatropic rearrangement reaction. The resulting chiral benzofuran products generated through this strategy exhibit significant 3D‐dimensionality and demonstrate ...
Lei Peng, Yu Chang, Liangchen Yin, Jinbang Zhang, Xuli Feng, Pengfei Wang, Wenling Qin, Hailong Yan   +7 more
wiley   +1 more source

Phase Transition in Halide Double Perovskites for Solar‐To‐Chemical Energy Conversion

Advanced Energy Materials, EarlyView.
Disorder‐to‐order phase transition in double perovskite Cs2AgBiBr6 eliminates self‐trapped excitons and antisite defects and promotes charge separation, with over sixfold photoactivity enhancement in photocatalytic C−H bond activation. Abstract Halide double perovskites have recently garnered significant interest in solar energy conversion applications
Chunhua Wang, Zhirun Xie, Pengshan Xie, Huiqiang Liang, Yang Ding, Yannan Wang, Michael K.H. Leung, Guosong Zeng, Johnny C. Ho, Sateesh Bandaru, Ning Han, Bao‐Lian Su, Yun Hau Ng   +12 more
wiley   +1 more source

Synthesis of the tetracyclic core of Illicium sesquiterpenes using an organocatalyzed asymmetric Robinson annulation

Beilstein Journal of Organic Chemistry, 2013
An enantioselective synthesis of the core framework of neurotrophic Illicium majucin-type sesquiterpenes is described here. This strategy is based on an organocatalyzed asymmetric Robinson annulation and provides an efficient approach for a diversity ...
Lynnie Trzoss, Jing Xu, Michelle H. Lacoske, Emmanuel A. Theodorakis   +3 more
doaj   +1 more source

Efficient Enantioselective Synthesis of Oxahelicenes Using Redox/Acid Cooperative Catalysts.

Journal of the American Chemical Society, 2016
An efficient and enantioselective synthesis of oxa[9]helicenes has been established via vanadium(V)-catalyzed oxidative coupling/intramolecular cyclization of polycyclic phenols.
M. Sako, Yoshiki Takeuchi, T. Tsujihara, J. Kodera, Tomikazu Kawano, S. Takizawa, H. Sasai   +6 more
semanticscholar   +1 more source

Synthetic Studies Directed Toward Streptenol D: Enantioselective Preparation of the 3,5-diacetoxy-6\u3cem\u3eE\u3c/em\u3e,8\u3cem\u3eE\u3c/em\u3e-decadiene Segment [PDF]

, 1998
The enantioselective preparation of 2-(3′R,5′R-diacetoxy-6E,8E-decadienyl)-1,3-dioxane, (+)-13, is described. This synthesis of the skeleton of streptenol D utilizes the ability of a diene-complexed (tricarbonyl)iron unit to serve as a protecting and ...
Dasgupta, Bireshwar, Donaldson, William
core   +1 more source

Biocatalytic Isocitrate Production from Low‐Concentration Gaseous CO2 and Biobased 2‐Oxogultarate

Advanced Energy and Sustainability Research, EarlyView.
Biocatalytic isocitrate production from 2‐oxoglutarate and low‐concentration CO2 below 5% in the presence of NADPH and manganese ion was developed. Isocitrate dehydrogenase (IDH) from yeast (EC 1.1.1.42) is an enzyme that catalyzes the decarboxylating isocitrate into 2‐oxogurtarate and carbon dioxide and the reverse process of the introducing carbon ...
Masamichi Hino, Yutaka Amao
wiley   +1 more source

Enantioselective Synthesis of Spirobarbiturate-Cyclohexenes through Phosphine-Catalyzed Asymmetric [4 + 2] Annulation of Barbiturate-Derived Alkenes with Allenoates.

Organic Letters, 2016
An enantioselective synthesis of pharmaceutically important spirobarbiturates has been achieved via spirocyclic chiral phosphine-catalyzed asymmetric [4 + 2] annulation of barbiturate-derived alkenes with allenoates.
Honglei Liu, Yang Liu, Chunhao Yuan, Guo-Peng Wang, Shou‐Fei Zhu, Yang Wu, Bo Wang, Zhanhu Sun, Yumei Xiao, Qi‐Lin Zhou, Hongchao Guo   +10 more
semanticscholar   +1 more source

Enantioselective Total Synthesis of (−)-Dactylolide

Organic Letters, 2006
[reaction: see text] The enantioselective total synthesis of (-)-dactylolide is reported. The absolute stereochemistry of the tetrahydropyran was established by catalytic asymmetric Jacobsen hetero-Diels-Alder reaction. The remote C19 stereocenter was introduced by a sequence of chelation-controlled Grignard addition and Ireland-Claisen rearrangement.
Louis, Ignace, L. Hungerford, Natasha, J. Humphries, Edward, D. McLeod, Malcolm   +3 more
openaire   +4 more sources

Pathway Complexity in Supramolecular Polymerization of Porphyrin Dyads for Kinetic Control of Helicity

Aggregate, EarlyView.
Supramolecular polymerization of porphyrin dyads (PDs) forms kinetically stable nanoparticles (PDParticle) via rapid cooling and thermodynamically stable fibrous polymers (PDFiber) via slow cooling. PDParticle gradually transforms into PDFiber. Introducing chiral alkyl chains induces helicity, with (S)‐PD favoring M helices and (R)‐PD favoring P ...
Hosoowi Lee, Yongho Lee, Minhyeong Lee, Dae Eun Kang, Jiwon Kim, Dong Ha Kim, Woo‐Dong Jang   +6 more
wiley   +1 more source

Photosensitizer Repositioning Affords an Enantiocomplementary Enzyme for [2 + 2]‐Cycloadditions

Angewandte Chemie, EarlyView.
In this study, we capitalize on the versatility offered by genetic code expansion to develop a proficient photoenzyme for [2 + 2]‐cycloadditions that is enantiocomplementary to our recently developed photoenzyme EnT1.3. By repositioning the genetically programmed benzophenone photosensitizer and subsequent directed evolution, we have developed an ...
Chuanjie Sun, Anna R. Kohn, Ross Smithson, Florence J. Hardy, Jonathan S. Trimble, Yuanxin Cao, Linus O. Johannissen, Sam Hay, Rebecca Crawshaw, Anthony P. Green   +9 more
wiley   +2 more sources