A mild heteroatom (O-, N-, and S-) methylation protocol using trimethyl phosphate (TMP)-Ca(OH)2 combination

Synthesis ◽  
2022 ◽  
Author(s):  
Yu Tang ◽  
Biao Yu
Keyword(s):  
Cost Efficiency ◽  
Room Temperature ◽  
High Efficiency ◽  
Attractive Alternative ◽  
Indole Derivatives ◽  
Trimethyl Phosphate ◽  
Environmental Friendly ◽  
Operational Simplicity

A mild heteroatom methylation protocol using trimethyl phosphate (TMP)-Ca(OH)2 combination has been developed, which proceeds in DMF, or water, or under neat conditions at 80 oC or at room temperature. A series of O-, N- and S-nucleophiles, including phenols, sulfonamides, N-heterocycles such as 9H-carbazole, indole derivatives, 1,8-naphthalimide, and aryl/alkyl thiols are suitable substrates of this protocol. The high efficiency, operational simplicity, scalability, cost-efficiency, and environmental friendly nature of this protocol make it an attractive alternative to the conventional base prompted heteroatom methylation procedures.

Efficient Synthesis of Indole Derivatives Containing the Tetrazole Moeity Utilizing an Ugi-Azide Post-Transformation Strategy

Synlett ◽  
2018 ◽  
Vol 29 (14) ◽  
pp. 1892-1896 ◽  
Author(s):  
Saeed Balalaie ◽  
Ali Nikbakht ◽  
Fatemeh Baghestani ◽  
Frank Rominger
Keyword(s):  
Room Temperature ◽  
Functional Group ◽  
Cyclization Reaction ◽  
Indole Derivatives ◽  
Efficient Synthesis ◽  
Efficient Strategy ◽  
High Yields ◽  
Operational Simplicity ◽  
Transformation Strategy

An efficient strategy has been developed for the synthesis of indole derivatives containing the tetrazole moiety using a AuCl3-catalyzed cyclization reaction. The precursors of the cycloadduct were easily prepared by an Ugi-azide 4-CR in methanol at room temperature. The merit of this protocol lies in its operational simplicity, readily available starting materials, high yields of product, and good functional group tolerance.

Clustering-Triggered Efficient Room Temperature Phosphorescence from Nonconventional Luminophores

2019 ◽  
Author(s):  
Shuyuan Zheng ◽  
Taiping Hu ◽  
Xin Bin ◽  
Yunzhong Wang ◽  
Yuanping Yi ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Efficiency ◽  
Spin Orbit Coupling ◽  
Design Rationale ◽  
Emission Mechanism ◽  
Room Temperature Phosphorescence ◽  
Electronic Interactions ◽  
Energy Gaps ◽  
Theoretical Results

Pure organic room temperature phosphorescence (RTP) and luminescence from nonconventional luminophores have gained increasing attention. However, it remains challenging to achieve efficient RTP from unorthodox luminophores, on account of the unsophisticated understanding of the emission mechanism. Here we propose a strategy to realize efficient RTP in nonconventional luminophores through incorporation of lone pairs together with clustering and effective electronic interactions. The former promotes spin-orbit coupling and boost the consequent intersystem crossing, whereas the latter narrows energy gaps and stabilizes the triplets, thus synergistically affording remarkable RTP. Experimental and theoretical results of urea and its derivatives verify the design rationale. Remarkably, RTP from thiourea solids with unprecedentedly high efficiency of up to 24.5% is obtained. Further control experiments testify the crucial role of through-space delocalization on the emission. These results would spur the future fabrication of nonconventional phosphors, and moreover should advance understanding of the underlying emission mechanism.<br>

Fast, high-efficiency, and homogeneous room-temperature cathodoluminescence of ZnO scintillator thin films on sapphire

2006 ◽  
Vol 89 (24) ◽  
pp. 243510 ◽  
Author(s):  
M. Lorenz ◽  
R. Johne ◽  
T. Nobis ◽  
H. Hochmuth ◽  
J. Lenzner ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
High Efficiency

A Characteristic-Featured Shock Wave Indicator for Simulating High-Speed Inviscid Flows on 3D Unstructured Mesh

2021 ◽  
Author(s):  
Yiwei Feng ◽  
Tiegang Liu ◽  
Xiaofeng He ◽  
Bin Zhang ◽  
Kun Wang
Keyword(s):  
Shock Wave ◽  
High Speed ◽  
Unstructured Mesh ◽  
High Efficiency ◽  
Flow Simulation ◽  
Attractive Alternative ◽  
Inviscid Flows ◽  
Speed Flow ◽  
Flow Compression ◽  
Shock Processing

Abstract In this work, we extend the characteristic-featured shock wave indicator based on artificial neuron training to 3D high-speed flow simulation on unstructured mesh. The extension is achieved through dimension splitting. This leads to that the proposed indicator is capable of identifying regions of flow compression in any direction. With this capability, the indicator is further developed to combine with h-adaptivity of mesh refinement to improve resolution with less computational costs. The present indicator provided an attractive alternative for constructing high-resolution, high-efficiency shock-processing method to simulate high-speed inviscid flows.

Barium calcium titanate @carbon hybrid materials for high-efficiency room-temperature pyrocatalysis

2021 ◽  
Author(s):  
Huiying Wang ◽  
Yanmin Jia ◽  
Taosheng Xu ◽  
Xiaoxin Shu ◽  
Yiming He ◽  
...  
Keyword(s):  
Hybrid Materials ◽  
Room Temperature ◽  
High Efficiency ◽  
Calcium Titanate

Control of a Supercritical CO2 Recompression Brayton Cycle Demonstration Loop

2013 ◽  
Author(s):  
T. Conboy ◽  
J. Pasch ◽  
D. Fleming
Keyword(s):  
Supercritical Co2 ◽  
High Efficiency ◽  
Power Conversion ◽  
Department Of Energy ◽  
Test Facility ◽  
Attractive Alternative ◽  
Commercial Development ◽  
Power Cycle ◽  
Test Loop ◽  
Recompression Cycle

The US Department of Energy is currently focused on the development of next-generation nuclear power reactors, with an eye towards improved efficiency and reduced capital cost. To this end, reactors using a closed-Brayton power conversion cycle have been proposed as an attractive alternative to steam turbines. The supercritical-CO2 recompression cycle has been identified as a leading candidate for this application as it can achieve high efficiency at relatively low operating temperatures with extremely compact turbomachinery. Sandia National Laboratories has been a leader in hardware and component development for the supercritical-CO2 cycle. With contractor Barber-Nichols Inc, Sandia has constructed a megawatt-class S-CO2 cycle test-loop to investigate the key areas of technological uncertainty for this power cycle, and to confirm model estimates of advantageous thermodynamic performance. Until recently, much of the work has centered on the simple S-CO2 cycle — a recuperated Brayton loop with a single turbine and compressor. However work has recently progressed to a recompression cycle with split-shaft turbo-alternator-compressors, unlocking the potential for much greater efficiency power conversion, but introducing greater complexity in control operations. The following sections use testing experience to frame control actions made by test loop operators in bringing the recompression cycle from cold startup conditions through transition to power generation on both turbines, to the desired test conditions, and finally to a safe shutdown. During this process, considerations regarding turbocompressor thrust state, CO2 thermodynamic state at the compressor inlet, compressor surge and stall, turbine u/c ratio, and numerous other factors must be taken into account. The development of these procedures on the Sandia test facility has greatly reduced the risk to industry in commercial development of the S-CO2 power cycle.

scholarly journals Design and durability study of environmental-friendly room-temperature processable icephobic coatings

2019 ◽  
Vol 355 ◽  
pp. 901-909 ◽  
Author(s):  
Xinghua Wu ◽  
Xin Zhao ◽  
Jeffrey Weng Chye Ho ◽  
Zhong Chen
Keyword(s):  
Room Temperature ◽  
Environmental Friendly

Modulating room temperature spin injection into GaN towards the high-efficiency spin-light emitting diodes

2020 ◽  
Vol 13 (4) ◽  
pp. 043006 ◽  
Author(s):  
Anke Song ◽  
Jiajun Chen ◽  
Jinshen Lan ◽  
Deyi Fu ◽  
Jiangpeng Zhou ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Efficiency ◽  
Light Emitting Diodes ◽  
Spin Injection ◽  
Light Emitting
Sign in / Sign up

Export Citation Format

Share Document