Alkoxymethylcyclosiloxanes - new efficient precursors of crystalline (CH3SiO3/2)8 silsesquioxane and polymethyl silsesquioxanes

AbstractA new, highly efficient and very simple method for the synthesis of pure octahedral methylsilsesquioxanes (CH3SiO3/2)8, from cyclic 2,4,6,8-tetraalkoxy- 2,4,6,8-tetramethylsiloxane, was developed. We have found that T8Me can be synthesized from a mixture of alkoxymethylcyclosiloxane isomers in the hydrolytic condensation process, utilizing an ionic catalyst - tetrabutylammonium fluoride (TBAF). The reaction was carried out under very mild conditions, at room temperature, in a variety of solvents of different polarity. A substantial solvent effect was observed. THF helped in the formation of pure T8Me, whereas in other solvents mixtures of T8Me and poly(methylsilsesquioxanes) (PMQS) of substantial degree of regularity, were obtained.

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Imidazole-induced self-assembly of polyoxovanadate cluster organic framework for efficient Knoevenagel condensation under mild conditions

CrystEngComm ◽

10.1039/d0ce00660b ◽

2020 ◽

Vol 22 (24) ◽

pp. 4147-4153 ◽

Cited By ~ 2

Author(s):

Ming-Yu Dou ◽

Dan-Dan Zhong ◽

Xian-Qiang Huang ◽

Guo-Yu Yang

Keyword(s):

Catalytic Activity ◽

Self Assembly ◽

Room Temperature ◽

Knoevenagel Condensation ◽

Solvent Free ◽

Mild Conditions ◽

Highly Efficient ◽

Organic Framework

Three new polyoxovanadates have been made, one of them displays highly efficient heterogeneous solvent-free catalytic activity and excellent recyclability in the Knoevenagel condensation at room temperature.

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Highly Efficient and Facile Method for Synthesis of 2-Substituted Benzimidazoles via Reductive Cyclization of O-Nitroaniline and Aryl Aldehydes

Organic Chemistry International ◽

10.1155/2012/498521 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Hossein Naeimi ◽

Nasrin Alishahi

Keyword(s):

Room Temperature ◽

Reaction Times ◽

Starting Material ◽

Reductive Cyclization ◽

Aryl Aldehydes ◽

Mild Conditions ◽

Highly Efficient ◽

Convenient Synthesis

A versatile and convenient synthesis of 2-substituted benzimidazoles, using o-nitroaniline as starting material with several aryl aldehydes, has been accomplished by using a small amount of a reluctant agent. The reaction was carried out under very mild conditions at room temperature. The yields obtained are very good in reasonably short reaction times.

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Brønsted Acid-Catalysed Allylic Amination of 1-(2-Aminoaryl)prop-2-en-1-ols to 1,2-Dihydroquinolines

Australian Journal of Chemistry ◽

10.1071/ch18191 ◽

2018 ◽

Vol 71 (9) ◽

pp. 673 ◽

Cited By ~ 1

Author(s):

David Philip Day ◽

Stuart Adam Henry ◽

Yichao Zhao ◽

Jianwen Jin ◽

Guy James Clarkson ◽

...

Keyword(s):

Room Temperature ◽

Trifluoromethanesulfonic Acid ◽

Catalyst Loading ◽

Synthetic Method ◽

Bronsted Acid ◽

Allylic Amination ◽

Mild Conditions ◽

Highly Efficient ◽

Brönsted Acid ◽

Wide Range

A highly efficient synthetic method to prepare 1,2-dihydroquinolines that relies on trifluoromethanesulfonic acid (TfOH)-catalysed allylic amination of 1-(2-aminoaryl)prop-2-en-1-ols is described. Achieved at a catalyst loading of 0.01 mol-% under mild conditions at room temperature, the reaction was found to be robust, with a wide range of substitution patterns tolerated. The corresponding N-heterocyclic adducts were obtained in good to excellent yields of 45–93 %.

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Titania supported synergistic palladium single atoms and nanoparticles for room temperature ketone and aldehydes hydrogenation

Nature Communications ◽

10.1038/s41467-019-13941-5 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 23

Author(s):

Long Kuai ◽

Zheng Chen ◽

Shoujie Liu ◽

Erjie Kan ◽

Nan Yu ◽

...

Keyword(s):

Green Chemistry ◽

Spray Pyrolysis ◽

Room Temperature ◽

Chemical Engineering ◽

Selective Reduction ◽

Single Atom ◽

Mild Conditions ◽

Single Atoms ◽

Highly Efficient ◽

Activity Enhancement

AbstractSelective reduction of ketone/aldehydes to alcohols is of great importance in green chemistry and chemical engineering. Highly efficient catalysts are still demanded to work under mild conditions, especially at room temperature. Here we present a synergistic function of single-atom palladium (Pd1) and nanoparticles (PdNPs) on TiO2 for highly efficient ketone/aldehydes hydrogenation to alcohols at room temperature. Compared to simple but inferior Pd1/TiO2 and PdNPs/TiO2 catalysts, more than twice activity enhancement is achieved with the Pd1+NPs/TiO2 catalyst that integrates both Pd1 and Pd NPs on mesoporous TiO2 supports, obtained by a simple but large-scaled spray pyrolysis route. The synergistic function of Pd1 and PdNPs is assigned so that the partial Pd1 dispersion contributes enough sites for the activation of C=O group while PdNPs site boosts the dissociation of H2 molecules to H atoms. This work not only contributes a superior catalyst for ketone/aldehydes hydrogenation, but also deepens the knowledge on their hydrogenation mechanism and guides people to engineer the catalytic behaviors as needed.

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Iodine-induced synthesis of sulfonate esters from sodium sulfinates and phenols under mild conditions

RSC Advances ◽

10.1039/c5ra00724k ◽

2015 ◽

Vol 5 (35) ◽

pp. 27439-27442 ◽

Cited By ~ 15

Author(s):

Jian Gao ◽

Xiaojun Pan ◽

Juan Liu ◽

Junyi Lai ◽

Liming Chang ◽

...

Keyword(s):

Transition Metal ◽

Efficient Method ◽

Room Temperature ◽

Metal Catalysts ◽

Transition Metal Catalysts ◽

Mild Conditions ◽

Highly Efficient

A facile and highly efficient method for the synthesis of sulfonate esters mediated by iodine at room temperature has been developed, without transition metal catalysts and oxidants.

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Metal β-diketonate complexes as highly efficient catalysts for chemical fixation of CO2 into cyclic carbonates under mild conditions

Dalton Transactions ◽

10.1039/c9dt03584b ◽

2019 ◽

Vol 48 (42) ◽

pp. 15970-15976 ◽

Cited By ~ 2

Author(s):

Hongmei Wang ◽

Zulei Zhang ◽

Hailong Wang ◽

Liping Guo ◽

Lei Li

Keyword(s):

Room Temperature ◽

Chemical Fixation ◽

Cyclic Carbonates ◽

Mild Conditions ◽

Highly Efficient

Metal β-diketonate complexes could efficiently catalyze the chemical fixation of CO2 at 1 atm and near room temperature.

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Copper-Catalyzed Highly Efficient Esterification of Aldehydes with N-Hydroxyphthalimide via Cross-Dehydrogenative Coupling in Water at Room Temperature

Synlett ◽

10.1055/s-0036-1588760 ◽

2017 ◽

Vol 28 (11) ◽

pp. 1321-1326 ◽

Cited By ~ 10

Author(s):

Can Jin ◽

Weike Su ◽

Zhicheng Guo ◽

Xinpeng Jiang ◽

Jiadi Zhou ◽

...

Keyword(s):

Reaction Time ◽

Efficient Method ◽

Room Temperature ◽

Coupling Reaction ◽

Short Reaction Time ◽

Mild Conditions ◽

Highly Efficient ◽

Dehydrogenative Coupling ◽

First Time

A copper-catalyzed cross-dehydrogenative coupling reaction between N-hydroxyphthalimide and aldehydes using PhI(OAc)2 as an oxidant is described. It is reported for the first time to synthesize NHPI esters in water, providing the corresponding NHPI esters in moderate to good yields. This facile and efficient method is eco-friendly and possesses the advantages of mild conditions, short reaction time, and broad substrate scope.

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SuFEx Activation with Ca(NTf2)2: A Unified Strategy to Access Sulfamides, Sulfamates and Sulfonamides from S(VI) Fluorides

10.26434/chemrxiv.12026811.v1 ◽

2020 ◽

Author(s):

Subham Mahapatra ◽

Cristian P. Woroch ◽

Todd W. Butler ◽

Sabrina N. Carneiro ◽

Sabrina C. Kwan ◽

...

Keyword(s):

Room Temperature ◽

Medicinal Chemistry ◽

Mild Conditions ◽

Broad Array

A method to activate sulfamoyl fluorides, fluorosulfates, and sulfonyl fluorides with calcium triflimide, and DABCO for SuFEx with amines is described. The reaction was applied to a diverse set of sulfamides, sulfamates, and sulfonamides at room temperature under mild conditions. Additionally, we highlight the application of this transformation to parallel medicinal chemistry to generate a broad array of nitrogen-based S(VI) compounds.

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