منابع مشابه
Microwave-assisted cyclizations promoted by polyphosphoric acid esters: a general method for 1-aryl-2-iminoazacycloalkanes
The first general procedure for the synthesis of 5 to 7-membered 1-aryl-2-iminoazacycloalkanes is presented, by microwave-assisted ring closure of ω-arylaminonitriles promoted by polyphosphoric acid (PPA) esters. 1-Aryl-2-iminopyrrolidines were easily prepared from the acyclic precursors employing a chloroformic solution of ethyl polyphosphate (PPE). The use of trimethylsilyl polyphosphate (PPS...
متن کاملWhy are trimethylsilyl groups asymmetrically coordinated? Gas-phase molecular structures of 1-trimethylsilyl-1,2,3-benzotriazole and 2-trimethylsilyl-1,3-thiazole.
The structures of 1-trimethylsilyl-1,2,3-benzotriazole and 2-trimethylsilyl-1,3-thiazole have been determined by gas electron diffraction and computational methods. While 1-trimethylsilyl-1,2,3-benzotriazole shows a significant asymmetry in the way the SiMe(3) groups bonds to the ring system, the same is not true for 2-trimethylsilyl-1,3-thiazole. However, it has been shown that when the positi...
متن کاملSodium terbium(III) polyphosphate
Single crystals of the title compound, NaTb(PO(3))(4), were obtained by solid-state reaction. This compound belongs to type II of long-chain polyphosphates with the general formula A(I)B(III)(PO(3))(4). It is isotypic with the NaNd(PO(3))(4) and NaEr(PO(3))(4) homologues. The crystal structure is built up of infinite crenelated chains of corner-sharing PO(4) tetra-hedra with a repeating unit of...
متن کاملBis-trimethylsilylcefamandole: an unusually stable trimethylsilyl-intermediate.
The preparation of crystalline bis-trimethylsilylcefamandole (7) and its utility in the preparation and purification of cefamandole are described. Although stable to solvolysis in isopropyl alcohol, 7 underwent smooth conversion to cefamandole in the presence of water, methanol, or ethanol.
متن کاملMass spectrometry of alditols as trimethylsilyl derivatives
The trimethylsilyl ethers of alditols with 3, 4, 5 and 6 carbon atoms were investigated. The mass spectra are unusually clearly correlated with the structures. The predominant fragmentations are cleavages in the carbon chain and rearrangement loss of trimethylsilanol. The spectra are closely related to those of the methyl ethers. A spectrum unambiguously identifies a compound as an alditol and ...
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ژورنال
عنوان ژورنال: Journal of Synthetic Organic Chemistry, Japan
سال: 1985
ISSN: 0037-9980,1883-6526
DOI: 10.5059/yukigoseikyokaishi.43.1163