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George Ferguson - One of the best experts on this subject based on the ideXlab platform.
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Triphenylsilanol 4 4 bipyridyl 4 1 the z 4 polymorph revisited
Acta Crystallographica Section C-crystal Structure Communications, 2013Co-Authors: Giovanni Luca Cascarano, George Ferguson, Carmelo Giacovazzo, Christopher Glidewell, Anthony L SpekAbstract:A fully ordered structure is reported for the polymorph of Triphenylsilanol-4,4'-bipyridyl (4/1), 4C18H16OSi·C10H8N2, having Z' = 4. The asymmetric unit contains four similar but distinct five-molecule aggregates, in which the central bipyridyl unit is linked to two molecules of Triphenylsilanol via O-H···N hydrogen bonds, with a further pair of Triphenylsilanol molecules linked to the first pair via O-H···O hydrogen bonds. An extensive series of C-H···π(arene) hydrogen bonds links these aggregates into complex sheets. This structure is compared with a previously reported structure [Bowes, Ferguson, Lough & Glidewell (2003). Acta Cryst. B59, 277-286], which was based on an erroneous disordered structural model arising from a false direct-methods solution with reference to a strong pseudo-inversion centre.
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hydrogen bonded adducts of Triphenylsilanol with diamines a finite ten molecule aggregate and chain sheet and framework structures built from o h o o h n and c h π arene hydrogen bonds
Acta Crystallographica Section B-structural Science, 2004Co-Authors: David E Turkington, George Ferguson, Alan J Lough, Christopher GlidewellAbstract:The structures of five hydrogen-bonded adducts of Triphenylsilanol, Ph3SiOH, with diamines have been determined. In the 4:1 adduct formed with 1,4-diazabicyclo[2.2.2]octane, (Ph3SiOH)4·C6H12N2 (I) (triclinic, P\bar 1, Z′ = 2), there are two independent five-component aggregates built from O—H⋯N and O—H⋯O hydrogen bonds, in one of which the diamine exhibits orientational disorder: these two aggregates are linked into a cyclic ten-molecule unit by means of two independent C—H⋯π(arene) hydrogen bonds. The 4:1 adduct formed with 1,2-bis(4-pyridyl)ethene, (Ph3SiOH)4·C12H10N2 (II) (triclinic, P\bar 1, Z′ = 0.5), forms a similar five-component aggregate which lies across a centre of inversion: a single C—H⋯π(arene) hydrogen bond links these aggregates into a molecular ladder. With N,N′-dimethylpiperazine, Triphenylsilanol forms a 2:1 adduct, (Ph3SiOH)2·C6H14N2 (III) (monoclinic, P21/c, Z′ = 0.5), in which a three-component aggregate built from O—H⋯N hydrogen bonds lies across a centre of inversion: two independent C—H⋯π(arene) hydrogen bonds link these aggregates into sheets. In the hydrated 2:1 adduct formed with 1,2-bis(4′-bipyridyl)ethane, (Ph3SiOH)2·C12H12N2·H2O (IV) (triclinic, P\bar 1, Z′ = 1), a combination of two independent O—H⋯O and two independent N—H⋯O hydrogen bonds links the five molecular components into a centrosymmetric eight-molecule aggregate, and six independent C—H⋯π(arene) hydrogen bonds link these chains into a continuous three-dimensional framework structure. In the dihydrated 2:1 adduct formed with 4,4′-bipyridyl, (Ph3SiOH)2·C10H8N2·(H2O)2 (V) (triclinic, P\bar 1, Z′ = 1), a combination of four independent O—H⋯O and two independent N—H⋯O hydrogen bonds links the five molecular components into a chain of rings, and four independent C—H⋯π(arene) hydrogen bonds link these chains into a continuous three-dimensional framework structure.
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the 1 1 adduct of Triphenylsilanol and 4 4 bipyridyl and three pairwise concomitant triclinic polymorphs of the 4 1 adduct having z 0 5 1 and 4
Acta Crystallographica Section B-structural Science, 2003Co-Authors: Katharine F Bowes, George Ferguson, Alan J Lough, Christopher GlidewellAbstract:Crystallization from methanol solution of mixtures of Triphenylsilanol and 4,4'-bipyridyl has given a 1:1 adduct (I), Ph(3)SiOH.C(10)H(8)N(2), and three polymorphic 4:1 adducts (II)-(IV), (Ph(3)SiOH)(4).C(10)H(8)N(2). In (I), the components are linked by a single O-H...N hydrogen bond and by a number of C-H...pi(arene) hydrogen bonds to form a continuous three-dimensional structure. Compounds (II)-(IV) are all triclinic, space group P-1, with Z' values of 0.5, 1 and 4, respectively. The basic hydrogen-bonded aggregate is the same in each of (II)-(IV), having a pair of silanol molecules linked to the bipyridyl via O-N...N hydrogen bonds and a further pair of silanol molecules linked to the first pair via O-H...O hydrogen bonds. In (II) there is just one such aggregate lying across a centre of inversion (Z' = 0.5) and in (III) there are two such aggregates, both lying across centres of inversion (Z' = 2 x 0.5 = 1). In (IV) there are six independent aggregates of this type, four of which lie across centres of inversion and two of which lie in general positions, so that Z' = (4 x 0.5) + 2 = 4. While the components in (I) are fully ordered, each of (II)-(IV) exhibits extensive disorder involving both the bipyridyl units and the phenyl rings of the silanol components.
Christopher Glidewell - One of the best experts on this subject based on the ideXlab platform.
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Triphenylsilanol 4 4 bipyridyl 4 1 the z 4 polymorph revisited
Acta Crystallographica Section C-crystal Structure Communications, 2013Co-Authors: Giovanni Luca Cascarano, George Ferguson, Carmelo Giacovazzo, Christopher Glidewell, Anthony L SpekAbstract:A fully ordered structure is reported for the polymorph of Triphenylsilanol-4,4'-bipyridyl (4/1), 4C18H16OSi·C10H8N2, having Z' = 4. The asymmetric unit contains four similar but distinct five-molecule aggregates, in which the central bipyridyl unit is linked to two molecules of Triphenylsilanol via O-H···N hydrogen bonds, with a further pair of Triphenylsilanol molecules linked to the first pair via O-H···O hydrogen bonds. An extensive series of C-H···π(arene) hydrogen bonds links these aggregates into complex sheets. This structure is compared with a previously reported structure [Bowes, Ferguson, Lough & Glidewell (2003). Acta Cryst. B59, 277-286], which was based on an erroneous disordered structural model arising from a false direct-methods solution with reference to a strong pseudo-inversion centre.
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hydrogen bonded adducts of Triphenylsilanol with diamines a finite ten molecule aggregate and chain sheet and framework structures built from o h o o h n and c h π arene hydrogen bonds
Acta Crystallographica Section B-structural Science, 2004Co-Authors: David E Turkington, George Ferguson, Alan J Lough, Christopher GlidewellAbstract:The structures of five hydrogen-bonded adducts of Triphenylsilanol, Ph3SiOH, with diamines have been determined. In the 4:1 adduct formed with 1,4-diazabicyclo[2.2.2]octane, (Ph3SiOH)4·C6H12N2 (I) (triclinic, P\bar 1, Z′ = 2), there are two independent five-component aggregates built from O—H⋯N and O—H⋯O hydrogen bonds, in one of which the diamine exhibits orientational disorder: these two aggregates are linked into a cyclic ten-molecule unit by means of two independent C—H⋯π(arene) hydrogen bonds. The 4:1 adduct formed with 1,2-bis(4-pyridyl)ethene, (Ph3SiOH)4·C12H10N2 (II) (triclinic, P\bar 1, Z′ = 0.5), forms a similar five-component aggregate which lies across a centre of inversion: a single C—H⋯π(arene) hydrogen bond links these aggregates into a molecular ladder. With N,N′-dimethylpiperazine, Triphenylsilanol forms a 2:1 adduct, (Ph3SiOH)2·C6H14N2 (III) (monoclinic, P21/c, Z′ = 0.5), in which a three-component aggregate built from O—H⋯N hydrogen bonds lies across a centre of inversion: two independent C—H⋯π(arene) hydrogen bonds link these aggregates into sheets. In the hydrated 2:1 adduct formed with 1,2-bis(4′-bipyridyl)ethane, (Ph3SiOH)2·C12H12N2·H2O (IV) (triclinic, P\bar 1, Z′ = 1), a combination of two independent O—H⋯O and two independent N—H⋯O hydrogen bonds links the five molecular components into a centrosymmetric eight-molecule aggregate, and six independent C—H⋯π(arene) hydrogen bonds link these chains into a continuous three-dimensional framework structure. In the dihydrated 2:1 adduct formed with 4,4′-bipyridyl, (Ph3SiOH)2·C10H8N2·(H2O)2 (V) (triclinic, P\bar 1, Z′ = 1), a combination of four independent O—H⋯O and two independent N—H⋯O hydrogen bonds links the five molecular components into a chain of rings, and four independent C—H⋯π(arene) hydrogen bonds link these chains into a continuous three-dimensional framework structure.
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the 1 1 adduct of Triphenylsilanol and 4 4 bipyridyl and three pairwise concomitant triclinic polymorphs of the 4 1 adduct having z 0 5 1 and 4
Acta Crystallographica Section B-structural Science, 2003Co-Authors: Katharine F Bowes, George Ferguson, Alan J Lough, Christopher GlidewellAbstract:Crystallization from methanol solution of mixtures of Triphenylsilanol and 4,4'-bipyridyl has given a 1:1 adduct (I), Ph(3)SiOH.C(10)H(8)N(2), and three polymorphic 4:1 adducts (II)-(IV), (Ph(3)SiOH)(4).C(10)H(8)N(2). In (I), the components are linked by a single O-H...N hydrogen bond and by a number of C-H...pi(arene) hydrogen bonds to form a continuous three-dimensional structure. Compounds (II)-(IV) are all triclinic, space group P-1, with Z' values of 0.5, 1 and 4, respectively. The basic hydrogen-bonded aggregate is the same in each of (II)-(IV), having a pair of silanol molecules linked to the bipyridyl via O-N...N hydrogen bonds and a further pair of silanol molecules linked to the first pair via O-H...O hydrogen bonds. In (II) there is just one such aggregate lying across a centre of inversion (Z' = 0.5) and in (III) there are two such aggregates, both lying across centres of inversion (Z' = 2 x 0.5 = 1). In (IV) there are six independent aggregates of this type, four of which lie across centres of inversion and two of which lie in general positions, so that Z' = (4 x 0.5) + 2 = 4. While the components in (I) are fully ordered, each of (II)-(IV) exhibits extensive disorder involving both the bipyridyl units and the phenyl rings of the silanol components.
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tetrameric Triphenylsilanol ph3sioh 4 and the adduct ph3sioh 2 di methyl sulfoxide both at 120 k and the adduct ph3sioh 4 1 4 dioxan at 150 k interplay of o h o and c h π arene interactions
Acta Crystallographica Section C-crystal Structure Communications, 2002Co-Authors: Katharine F Bowes, Christopher Glidewell, John N LowAbstract:The structure of tetrameric triphenylsilanol, C18H16OSi, (I), has been re-investigated at 120 (2) K. The hydroxyl H atoms were readily located and one of the arene rings is disordered over two closely positioned sets of sites. The molecules are linked into cyclic tetramers, having approximate \overline 4 (S4) symmetry, via O—H⋯O hydrogen bonds [H⋯O 1.81–1.85 A, O⋯O 2.634 (3)–2.693 (3) A and O—H⋯O 156–166°]. At ambient temperature, there are indications of multiple disorder of the phenyl-ring sites. In bis(triphenylsilanol) dimethyl sulfoxide solvate, 2C18H16OSi·C2H6OS, (II), the dimethyl sulfoxide component is disordered across a twofold rotation axis in C2/c, and the molecular components are linked by a single O—H⋯O hydrogen bond [H⋯O 1.85 A, O⋯O 2.732 (2) A and O—H⋯O 172°] into three-molecule aggregates, which are themselves linked into a single three-dimensional framework by two C—H⋯π(arene) interactions. In tetrakis(triphenylsilanol) 1,4-dioxan solvate, 4C18H16OSi·C4H8O2, (III), the 1,4-dioxan component lies across an inversion centre in space group P\overline 1 and centrosymmetric five-molecule aggregates are linked by paired C—H⋯π(arene) interactions to form molecular ladders.
Haiming Guo - One of the best experts on this subject based on the ideXlab platform.
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organocatalytic enantioselective allylic etherification of morita baylis hillman carbonates and silanols
Journal of Organic Chemistry, 2016Co-Authors: Huili Liu, Mingsheng Xie, Haiming GuoAbstract:The organocatalytic asymmetric allylic etherification reaction of Morita–Baylis–Hillman carbonates and silanols was reported for the first time. With modified cinchona alkaloid (DHQD)2PYR as the catalyst, a series of aromatic, heterocyclic, or aliphatic Morita–Baylis–Hillman carbonates (25 examples) worked well with Triphenylsilanol, affording the corresponding products in moderate to good yields (up to 98%), high regioselectivities (>20:1), and good enantioselectivities (up to 92%). When dimethylphenylsilanol was used as the nucleophile, the product was obtained in 60% yield and 87% ee.
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Organocatalytic Enantioselective Allylic Etherification of Morita–Baylis–Hillman Carbonates and Silanols
2016Co-Authors: Huili Liu, Mingsheng Xie, Haiming GuoAbstract:The organocatalytic asymmetric allylic etherification reaction of Morita–Baylis–Hillman carbonates and silanols was reported for the first time. With modified cinchona alkaloid (DHQD)2PYR as the catalyst, a series of aromatic, heterocyclic, or aliphatic Morita–Baylis–Hillman carbonates (25 examples) worked well with Triphenylsilanol, affording the corresponding products in moderate to good yields (up to 98%), high regioselectivities (>20:1), and good enantioselectivities (up to 92%). When dimethylphenylsilanol was used as the nucleophile, the product was obtained in 60% yield and 87% ee
Huili Liu - One of the best experts on this subject based on the ideXlab platform.
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organocatalytic enantioselective allylic etherification of morita baylis hillman carbonates and silanols
Journal of Organic Chemistry, 2016Co-Authors: Huili Liu, Mingsheng Xie, Haiming GuoAbstract:The organocatalytic asymmetric allylic etherification reaction of Morita–Baylis–Hillman carbonates and silanols was reported for the first time. With modified cinchona alkaloid (DHQD)2PYR as the catalyst, a series of aromatic, heterocyclic, or aliphatic Morita–Baylis–Hillman carbonates (25 examples) worked well with Triphenylsilanol, affording the corresponding products in moderate to good yields (up to 98%), high regioselectivities (>20:1), and good enantioselectivities (up to 92%). When dimethylphenylsilanol was used as the nucleophile, the product was obtained in 60% yield and 87% ee.
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Organocatalytic Enantioselective Allylic Etherification of Morita–Baylis–Hillman Carbonates and Silanols
2016Co-Authors: Huili Liu, Mingsheng Xie, Haiming GuoAbstract:The organocatalytic asymmetric allylic etherification reaction of Morita–Baylis–Hillman carbonates and silanols was reported for the first time. With modified cinchona alkaloid (DHQD)2PYR as the catalyst, a series of aromatic, heterocyclic, or aliphatic Morita–Baylis–Hillman carbonates (25 examples) worked well with Triphenylsilanol, affording the corresponding products in moderate to good yields (up to 98%), high regioselectivities (>20:1), and good enantioselectivities (up to 92%). When dimethylphenylsilanol was used as the nucleophile, the product was obtained in 60% yield and 87% ee
R C Mehrotra - One of the best experts on this subject based on the ideXlab platform.
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synthesis and characterization of some unique heterocyclic derivatives containing aluminium iii atoms in 4 and 6 co ordination states reaction of bis β diketonato aluminium iii di μ isopropoxo di isopropoxo aluminium iii with Triphenylsilanol and diphenylsilanediol
Journal of Coordination Chemistry, 2002Co-Authors: Shweta Nagar, Anita Dhammani, R Bohra, R C MehrotraAbstract:Reactions of bis ( g -diketonato) aluminium(III)-di- w -isopropoxo-di-isopropoxo-aluminium (III), [CH3COCHCOR)2Al( w -OPri)2Al(OPri) 2], with Triphenylsilanol, Ph3SiOH, in 1:1 and 1:2 molar ratios and with diphenylsilanediol, Ph2Si(OH)2, in a 1:1 molar ratio, have resulted in the synthesis of [(CH3COCHCOR)2Al( w -OPri)2Al(OSiPh3)(OPri)], [(CH3COCHCOR)2Al( w -OPri)2Al(OSiPh3)2] and [(CH3COCHCOR)2Al( w -OPri)2Al(OSiPh2O], respectively. These are soluble in a variety of organic solvents ( e.g. , benzene, chloroform and dimethylsulfoxide) and show dinuclear behaviour in chloroform. These derivatives have been characterized by elemental analyses, molecular weight measurements, IR and NMR (1H, 13C and 27Al) studies.
