- A simple and efficient room temperature silylation of diverse functional groups with hexamethyldisilazane using CeO2 nanoparticles as solid catalysts
-
In this study, a mild and efficient method is developed for the silylation of diverse functional groups using CeO2 nanoparticles (n-CeO2) as solid catalysts with hexamethyldisilazane (HMDS) as silylating agent at room temperature. Alcohols, phenols and acids are silylated to their respective silyl derivatives with faster reaction rate while amines and thiols required relatively longer reaction time. Moreover, the solid catalyst is easily be separated from the reaction mixture and recycled more than five times without any obvious decay in its activity. Powder X-ray diffraction (XRD), transmission electron microscope (TEM), UV–vis diffuse reflectance spectra (UV-DRS) and Raman analyses revealed identical structural integrity, particle size, absorption edge and valence state for the reused solid compared to the fresh solid catalyst.
- Anbu, Nagaraj,Vijayan, Chellappa,Dhakshinamoorthy, Amarajothi
-
-
- Stoichiometric Reactions of CO2 and Indium-Silylamides and Catalytic Synthesis of Ureas
-
The indium compounds In(N(SiMe3)2)2Cl?THF (2) and In(N(SiMe3)2)Cl2?(THF)n (3) were shown to react with CO2 to give [(Me3Si)2N)InX(μ-OSiMe3)]2 (X=N(SiMe3)2 4, Cl 5). 0.05–2.0 mol % of the species 3 acts as a pre-catalyst for the conversion of aryl and alkyl silylamines under CO2 (2–3 atm) to give the corresponding ureas in 70–99 % yields. A proposed mechanism is supported by experimental and computational data.
- Xu, Maotong,Jupp, Andrew R.,Stephan, Douglas W.
-
supporting information
p. 14277 - 14281
(2017/10/31)
-
- Novel method for preparing bis(trimethylsilyl) amines via treatment with trimethylsilylamines and methyl iodide
-
A convenient method for the synthesis of N,N-bis(trimethylsilyl)alkylamines has been reported. N-(Trimethylsilyl)diethylamine incorporated with a stoichiometric amount of methyl iodide was effective to convert primary amines, especially aromatic amines, and their monotrimethylsilyl derivatives into the corresponding N,N-bis(trimethylsilyl)amine derivatives in high yields. In the case of N-trimethylsilyl derivatives of aliphatic primary amines, a half-amount of silylamines served as a silylation agent against another half-amount of silylamines in the presence of 0.5 equivalent of methyl iodide to give N,N-bis(trimethylsilyl)alkylamines in good yield. Allyl iodide, allyl bromide and benzyl bromide were also effective to promote the silylation activity of silylamines.
- Hamada, Yoshitaka,Yamamoto, Yasushi,Shimizu, Hideaki
-
-
- Metal-assisted fragmentation of N-aryl- and -alkyl-N-trimethylsilylaminosulfur chlorides and N-aryl- and -alkyl-aminosulfur chlorides in the presence of conjugated dienes: Synthesis and reactivity of 2-substituted-3,6-dihydro-1,2-thiazines
-
N-Alkyl- and -aryl-N-trimethylsilylaminosulfur chlorides 2 and N-aryl- and -alkyl-aminosulfur chlorides 8 fragment in the presence of silver ions and a conjugated diene to yield 2-substituted-3,6-dihydro-1,2-thiarines 6 as the major products, possibly via
- Bryce, Martin R.,Chesney, Antony,McKelvey, Graham N.,Batsanov, Andrei S.,Howard, Judith A. K.,Anderson, Martin
-
p. 1825 - 1831
(2007/10/03)
-
- Generation of Thionitrosoarenes (ArN=S) from N-(Arylaminothio)phthalimides and in situ Trapping with Alkenes and Conjugated Dienes
-
A series of N-(arylaminothio)phthalimide derivatives (7a-h) has been prepared by reaction of phthalimidesulphenyl chloride with the trimethylsilyl derivative of the appropriate arylamine.On treatment with triethylamine at room temperature, compounds (7) fragment to yield transient thionitroso species (8).Derivatives (8a-h) have been trapped in good yield as their Diels-Alder adducts with the following conjugated dienes: butadiene, 2.3-dimethylbutadiene, 1.4-diphenylbutadiene, (E,E)- and (E,Z)-hexa-2,4-diene, 1,1'-bicyclopentenyl (25) and 1,1'-bicyclohexenyl (26).The stereochemistry of the diene is retained in the adducts (19)-(24).Thionitrosoarene derivatives (8) also afford sulphenamide derivatives, e.g. (11) and (12)-(16), by ene addition to dimethylbutadiene, isobutene, and α-methylstyrene.N-Aryliminosulphur dichlorides (34) react with 2,3-dimethylbutadiene to yield 1,2-thiazine and sulphenamide products, probably by way of thionitrosoarene intermediates.
- Bryce, Martin R.,Taylor, Paul C.
-
p. 3225 - 3235
(2007/10/02)
-
- NOVEL TRICHLOROACETYL BASED SILYLATIONS: SIMPLE METHODS FOR t-BUTYLDIMETHYLSILYLATIONS AND FOR THE PROTECTION OF AMINO GROUPS.
-
A new reagent for t-butyldimethylsilylation has been developed and the known trimethylsilyl trichloroacetate (1) has been shown to be of use for N-silylating amines.
- Galan, Adam A.,Lee, Thomas V.,Chapleo, Christopher B.
-
p. 4995 - 4998
(2007/10/02)
-
- Synthesis of Disiloxanediyl Diamines via a Facile Homocondensation of Amino Silanols
-
1,3-Bis(4-isocyanatophenyl)-1,3-dimethyl-1,3-diphenyldisiloxane (1a) and 1,3-bis(4-isocyanatophenyl)-1,1,3,3-tetramethyldisiloxane (1b) were synthesized in six steps from 4-bromoaniline (2) in 57percent and 55percent overall yields, respectively.The key s
- Weisenfeld, Robert B.
-
p. 2434 - 2436
(2007/10/02)
-