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41.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(1):m1-m4
In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,2‐bis(4‐pyridyl)ethene (1/1), [Fe(C18H15O)2]·C12H10N2, there is an intramolecular O—H?O hydrogen bond in the ferrocenediol component and a single O—H?N hydrogen bond linking the diol to the diamine, which is disordered over two sets of sites, so forming a finite monomeric adduct. In the adduct ferrocene‐1,1′‐diylbis(diphenylmethanol)–1,6‐diaminohexane (2/1), 2[Fe(C18H15O)2]·C6H16N2, the amine lies across a centre of inversion in space group P. There is an intramolecular O—H?O hydrogen bond in the ferrocenediol, and the molecular components are linked by O—H?N and N—H?O hydrogen bonds, one of each type, into a C(13)[R(12)] chain of rings. 相似文献
42.
Ratna Dasgupta Pranab R. Kanjilal Swapan K. Patra Manish Sarkar Usha Ranjan Ghatak 《Tetrahedron》1985,41(23):5619-5625
The efficacy of a new acid-catalyzed intramolecular C-alkylation has been demonstrated by the synthesis of 1-methyl-4--methoxyphenylbicyclo [2.2.2] octan-2-one () and 4--methoxyphenylbicyclo [2.2.2] octan-2-one () from easily accessible starting materials. The carbinol , derived from , undergoes facile rearrangement leading to 1--methoxyphenyl-4-methyl bicyclo [3.2.1] oct-3-ene (), which has been transformed to -1--methoxyphenyl-4-methylbicyclo [3.2.1] octan-3-one (). 相似文献
43.
Choudhury M. Zakaria George Ferguson Alan J. Lough Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(4):o204-o208
The adduct 1,6‐diaminohexane–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2) is a salt {hexane‐1,6‐diyldiammonium–4‐[1,1‐bis(4‐hydroxyphenyl)ethyl]phenolate (1/2)}, C6H18N22+·2C20H17O3?, in which the cation lies across a centre of inversion in space group P. The anions are linked by two short O—H?O hydrogen bonds [H?O 1.74 and 1.76 Å, O?O 2.5702 (12) and 2.5855 (12) Å, and O—H?O 168 and 169°] into a chain containing two types of R(24) ring. Each cation is linked to four different anion chains by three N—H?O hydrogen bonds [H?O 1.76–2.06 Å, N?O 2.6749 (14)–2.9159 (14) Å and N—H?O 156–172°]. In the adduct 2,2′‐bipyridyl–1,1,1‐tris(4‐hydroxyphenyl)ethane (1/2), C10H8N2·2C20H18O3, the neutral diamine lies across a centre of inversion in space group P21/n. The tris(phenol) molecules are linked by two O—H?O hydrogen bonds [H?O both 1.90 Å, O?O 2.7303 (14) and 2.7415 (15) Å, and O—H?O 173 and 176°] into sheets built from R(38) rings. Pairs of tris(phenol) sheets are linked via the diamine by means of a single O—H?N hydrogen bond [H?N 1.97 Å, O?N 2.7833 (16) Å and O—H?N 163°]. 相似文献
44.
Oğul Esen Anindya Ghose Choudhury Partha Guha Hasan Gümral 《Regular and Chaotic Dynamics》2016,21(2):175-188
Degenerate tri-Hamiltonian structures of the Shivamoggi and generalized Raychaudhuri equations are exhibited. For certain specific values of the parameters, it is shown that hyperchaotic Lü and Qi systems are superintegrable and admit tri-Hamiltonian structures. 相似文献
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Shrivats Semwal Dr. Joyanta Choudhury 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(20):5648-5652
Disclosed here is a molecular switch which responds to acid-base stimuli and serves as a bi-state catalyst for two different reactions. The two states of the switch serve as a highly active and poorly active catalyst for two catalytic reactions (namely a hydrogenation and a dehydrogenative coupling) but in a complementary manner. The system was used in an assisted tandem catalysis set-up involving dehydrogenative coupling of an amine and then hydrogenation of the resulting imine product by switching between the respective states of the catalyst. 相似文献
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