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81.
Loh ED 《Physical review letters》1986,57(22):2865-2867
82.
Aldol reaction under solvent-free conditions: highly stereoselective synthesis of 1,3-amino alcohols
[formula: see text] A method for the highly stereoselective synthesis of 1,3-amino alcohols based on the indium trichloride-catalyzed Mukaiyama aldol reaction of keto ester (R,S)-1 under solvent-free conditions has been developed. The high selectivity observed can be explained on the basis of the shielding of one face by a remote substituent. 相似文献
83.
Ilknur Yildirim Sarah Crotty Claas H. Loh Grit Festag Christine Weber Pier‐Francesco Caponi Michael Gottschaldt Matthias Westerhausen Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2016,54(3):437-448
A simple and convenient method for the synthesis of end functionalized polylactides (PLAs) under mild conditions by ring opening polymerization (ROP) in the absence of potentially toxic catalysts is described. Various alcohols were used as initiators in combination with Ca[N(SiMe3)2]2(THF)2 as the precatalyst in THF at room temperature. Tailored end functionalities were obtained in a controlled fashion. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐ToF‐MS) and electrospray ionization quadrupole time of flight mass spectrometry (ESI‐Q‐ToF‐MS) analysis were performed to investigate the end groups. The results confirmed that the end group fidelity was maintained in the isolated PLAs. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 437–448 相似文献
84.
85.
86.
Selective Alkenylation and Hydroalkenylation of Enol Phosphates through Direct C?H Functionalization
Xu‐Hong Hu Xiao‐Fei Yang Teck‐Peng Loh 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(51):15755-15759
An efficient and selective Rh‐catalyzed direct C H functionalization reaction of enol phosphates was developed. The method is applicable to a variety of coupling partners, including activated alkenes, alkynes, and allenes, and leads to the formation of various valuable alkenylated and hydroalkenylated enol phosphates through the action of the phosphate directing group. The versatility and utility of the coupling products were demonstrated through further transformations into synthetically useful building blocks. 相似文献
87.
88.
Recent advances in host–guest chemistry have significantly influenced the construction of supramolecular soft biomaterials. The highly selective and non‐covalent interactions provide vast possibilities of manipulating supramolecular self‐assemblies at the molecular level, allowing a rational design to control the sizes and morphologies of the resultant objects as carrier vehicles in a delivery system. In this Focus Review, the most recent developments of supramolecular self‐assemblies through host–guest inclusion, including nanoparticles, micelles, vesicles, hydrogels, and various stimuli‐responsive morphology transition materials are presented. These sophisticated materials with diverse functions, oriented towards therapeutic agent delivery, are further summarized into several active domains in the areas of drug delivery, gene delivery, co‐delivery and site‐specific targeting deliveries. Finally, the possible strategies for future design of multifunctional delivery carriers by combining host–guest chemistry with biological interface science are proposed. 相似文献
89.
Unprecedented Acid‐Promoted Polymerization and Gelation of Acrylamide: A Serendipitous Discovery 下载免费PDF全文
Siew Yin Chan Dr. Shermin S. Goh Dr. Qingqing Dou Benjamin Qi Yu Chan Dr. Wee Sim Choo Prof. David James Young Prof. Xian Jun Loh 《化学:亚洲杂志》2018,13(14):1797-1804
Dilute acid polymerizes degassed, aqueous acrylamide with concomitant gelation, without the need for added free radical initiator or cross‐linking agent. This reaction is accelerated by sonication or UV irradiation, but inhibited by adventitious oxygen or the addition of a free radical inhibitor, suggesting an acid‐accelerated free radical process. The resulting hydrogels are thixotropic in nature and partially disrupted by the addition of chaotropic agents, indicating the importance of hydrogen bonding to the 3D network. This discovery was made while trying to prepare pectin‐polyacrylamide hydrogels. We observed that pectin initiated the gelation of acrylamide, but only if the aqueous pectin samples had a pH lower than ca. 5. 相似文献
90.
In(III) complexes efficiently catalyse asymmetric Mannich-type reactions in ionic liquids with high diastereoselectivity and good yield. 相似文献