- Catalytic cycloaminomethylation of ureas and thioureas with N,N-bis(methoxymethyl)alkanamines
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An efficient procedure has been developed for the synthesis of 5-alkyl-1,3,5-triazinan-2-ones, 5-alkyl-1,3,5-triazinane-2-thiones, and 2,6-dialkylhexahydro-2,3a,4a,6,7a,8a-hexaazacyclopenta[def]fluorene-4,8(1H,5H)-diones by reactions of urea, thiourea, an
- Khairullina,Geniyatova,Meshcheryakova,Khalilov,Ibragimov,Dzhemilev
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- Synthesis and structures of a new class of calixarene analogs derived from 5-t-butyltetrahydro-1,3,5-triazine-2(1H)one
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Representative members of a novel class of calizarene analogs derived from 5-t-butyltetrahydro-1,3,5-triazine-2(1H)one 1 have been synthesized and their structures and conformations investigated by X-ray crystallography and NMR spectroscopy.
- Dave,Doyle,Axenrod,Yazdekhasti,Ammon
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- Hydrolysis of 7,7-substituted derivatives of 3-tert-butyl-3,4-dihydro-2H- thiazolo-[3,2-a][1,3,5]triazin-6(7H)-one
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Alkaline hydrolysis of 3-tert-butyl-7,7-bis(hydroxymethyl)-3,4-dihydro-2H- thiazolo[3,2-a][1,3,5]-triazin-6(7H)-one can occur in three directions: with cleavage of the tetrahydrotriazine ring, with cleavage of the thiazolidine ring, and also with opening of both rings. Depending on the process conditions, either the hydrolysis product corresponding to the first direction or the hydrolytic decomposition products corresponding to the second and third directions can be obtained in preparative quantities. Hydrolysis of 3,3′-di-tert-butyl-3′,4′-dihydro-2′ H-spiro[(perhydro-1, 3-oxazine)-5,7′-thiazolo[3,2-a][1,3,5]triazin]-6′-one in (NH 4)2CO3 solution occurs in two steps: in the first step, cleavage of the tetrahydrotriazine ring occurs; and in the second step, opening of the perhydrooxazine ring occurs. 2005 Springer Science+Business Media, Inc.
- Ramsh,Ivanenko,Shpilevyi,Medvedskiy,Kushakova
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- Rational construction of macrocycles consisting of methylene bridged ureas
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Synthesis of two macrocycles formed by urea functions connected solely by methylene bridges is described. This is the first example of isolated and fully characterized macrocyclic compounds in which NH-containing urea units are separated by methylene bridges. X-ray diffractometry revealed formation of multiple intramolecular hydrogen bonds between acidic NH and oxygen atoms of urea within the macrocycles.
- Yawer, Mirza Arfan,Necas, Marek,Sindelar, Vladimir
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- Investigation of steric influences on hydrogen-bonding motifs in cyclic ureas by using X-ray, neutron, and computational methods
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A series of urea-derived heterocycles, 5N-substituted hexahydro-1,3,5- triazin-2-ones, has been prepared and their structures have been determined for the first time. This family of compounds only differ in their substituent at the 5-position (which is derived from the corresponding primary amine), that is, methyl (1), ethyl (2), isopropyl (3), tert-butyl (4), benzyl (5), N,N-(diethyl)ethylamine (6), and 2-hydroxyethyl (7). The common heterocyclic core of these molecules is a cyclic urea, which has the potential to form a hydrogen-bonding tape motif that consists of self-associative R2 2(8) dimers. The results from X-ray crystallography and, where possible, Laue neutron crystallography show that the hydrogen-bonding motifs that are observed and the planarity of the hydrogen bonds appear to depend on the steric hindrance at the α-carbon atom of the N substituent. With the less-hindered substituents, methyl and ethyl, the anticipated tape motif is observed. When additional methyl groups are added onto the α-carbon atom, as in the isopropyl and tert-butyl derivatives, a different 2D hydrogen-bonding motif is observed. Despite the bulkiness of the substituents, the benzyl and N,N-(diethyl)ethylamine derivatives have methylene units at the α-carbon atom and, therefore, display the tape motif. The introduction of a competing hydrogen-bond donor/acceptor in the 2-hydroxyethyl derivative disrupts the tape motif, with a hydroxy group interrupting the N-H×××O-C interactions. The geometry around the hydrogen-bearing nitrogen atoms, whether planar or non-planar, has been confirmed for compounds 2 and 5 by using Laue neutron diffraction and rationalized by using computational methods, thus demonstrating that distortion of O-C-N-H torsion angles occurs to maintain almost-linear hydrogen-bonding interactions. The incredible bulk: A series of cyclic ureas has been studied to examine the influence of bulky substituents on the hydrogen-bonding motifs that form and the degree to which the urea group can be distorted to maintain strong intermolecular contacts. Copyright
- McCormick, Laura J.,McDonnell-Worth, Ciaran,Platts, James A.,Edwards, Alison J.,Turner, David R.
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p. 2642 - 2651
(2013/11/19)
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- Synthesis of 5-alkyl-1,3,5-triazinan-2-ones and 5-alkyl-1,3,5-triazinane-2- thiones using Cu- and Sm-containing catalysts
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Efficient procedures have been developed for the synthesis of 5-alkyl-1,3,5-triazinan-2-ones and 5-alkyl-1,3,5-triazinane-2-thiones by reaction of urea (thiourea) with primary alkylamines and N,N,N′,N′- tetramethylmethylenediamine and by reaction of prima
- Khairullina,Geniyatova,Ibragimov,Dzhemilev
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p. 904 - 908
(2013/07/26)
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- AMINOMETHYLATION OF UREA DERIVATIVES BY N-METHYLENE-TERT-BUTYLAMINE. N-MONOSUBSTITUTED AND N,N-DISUBSTITUTED UREAS
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The reaction of N-methylene-tert-butylamine with N-monosubstituted ureas is a reaction of the Mannich type and leads to the formation of 1-R-5-tert-butyl-3,4,5,6-tetrahydro-1,3,5-triazin-2-ones and tert-butylamine.The analogous reaction of N,N-disubstituted ureas leads to the production of linear Mannich bases (1,5-diureido-3-tert-butyl-1,3,5-triazapentanes).
- Kovalenko, A. L.,Serov, Yu. V.,Tselinskii, I. V.,Nikonov, A. A.
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p. 2120 - 2123
(2007/10/02)
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