Selective O-Demethylation of 5,8-Dihydroxy-2,3-Dimethoxy-6-Methylnaphtho-1,4-Quinone: The Crystal Structures of 5,8-Dihydroxy-2,3-Dimethoxy-6-Methylnaphtho-1,4-Quinone and 2,5,8-Triacetoxy-3-Methoxy-6-Methylnaphtho-1,4-Quinone

1987 ◽  
Vol 40 (7) ◽  
pp. 1191 ◽  
Author(s):  
JR Cannon ◽  
Y Matsuki ◽  
VA Patrick ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Sodium Hydroxide ◽  
Crystal Structures ◽  
Hydrolysis Product ◽  
Aqueous Sodium Hydroxide ◽  
X Ray Diffraction ◽  
Aqueous Sodium ◽  
X Ray ◽  
Least Squares Techniques

It has been confirmed that treatment of 5,8-dihydroxy-2,3-dimethoxy-6-methylnaphtho-1,4- quinone (1) with dilute aqueous sodium hydroxide leads to selective O- demethylation. The hydrolysis product has been identified as 2,5,8-trihydroxy-3-methoxy-6-methylnaphtho1,4- quinone (3) from the crystal structure of the corresponding triacetate (4). The crystal structures of 5,8-dihydroxy-2,3-dimethoxy-6-methylnaphtho-1,4-quinone (1) and 2,5,8-triacetoxy-3-methoxy-6-methylnaphtho-1,4-quinone (4) were determined by X-ray diffraction; diffractometer data at 295 K were refined by least squares techniques to residuals of 0.074 (583 'observed' reflections) for (1) and 0.049 (2005) for (4). Crystals of (1) are monoclinic, P2l/c, a 3.873(4), b 20.21(1), c 15.OO(2) �, β 96.05(6)�, Z 4. Crystals of (4) are also monoclinic, P2l/c, a 10.532(5), b 14.596(6), c 12.097(6) �, β 109.74(4)�, Z 4.

Orthoamide und Iminiumsalze, LXXIX [1]. N-[w-(Dimethylamino)alkyl]-N´,N´,N´´,N´´-tetramethylguanidine und davon abgeleitete Guanidiniumsalze: Synthese und Kristallstrukturen/ Orthoamides and Iminium Salts, LXXIX [1]. N-[w-(Dimethylamino)alkyl]-N´,N´,N´´,N´´- tetramethylguanidines and Salts Derived therefrom: Synthesis and Crystal Structures

2012 ◽  
Vol 67 (7) ◽  
pp. 685-698 ◽  
Author(s):  
Ioannis Tiritiris ◽  
Willi Kantlehner
Keyword(s):  
Sodium Hydroxide ◽  
Crystal Structures ◽  
Dimethyl Sulfate ◽  
Aqueous Sodium Hydroxide ◽  
Chloride Ions ◽  
Sodium Tetraphenylborate ◽  
X Ray Diffraction ◽  
Aqueous Sodium ◽  
X Ray ◽  
Iminium Salts

N-(ω-Dimethylammonioalkyl)-N´,N´,N´´,N´´-tetramethylguanidinium-dichlorides 5a, b are obtained from the chloroformamidinium salt 2 and diamines 3a, b. Their crystal structures reveal that the guanidinium ions are associated with the chloride ions via N-H· · ·Cl hydrogen bonds. By deprotonation of 5a, b with one equivalent of sodium hydroxide, the guanidinium chlorides 4a, b are accessible, and a further deprotonation leads to the aminoguanidines 6a, b, which hydrolyze in the presence of excessive aqueous sodium hydroxide to give the aminoalkylureas 7a, b. The salts 9a, b and 10a, b were synthesized from 4a, b and 5a, b, respectively, by anion metathesis by means of sodium tetraphenylborate. 7a reacts with dimethyl sulfate to give the waxy ammonium salt 11a, which was converted to the crystalline tetraphenylborate salt 12a. The crystal structures of all the tetraphenylborates were determined by single-crystal X-ray diffraction analysis.

Crystal structure of 2,3-Dichloro-5,8-dihydroxynaphtho-1,4-quinone

1978 ◽  
Vol 31 (3) ◽  
pp. 555 ◽  
Author(s):  
GI Feutrill ◽  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Least Squares ◽  
Benzene Ring ◽  
Title Compound ◽  
X Ray Diffraction ◽  
Hydrogen Atoms ◽  
X Ray ◽  
The One ◽  
Least Squares Techniques

The crystal structure of the title compound has been determined at 295 K by single-crystal X-ray diffraction methods and refined by least- squares techniques to a residual of 0.049 for 1046 'observed' reflections. Crystals are monoclinic, P21/c, a 11.584(6), b 5.449(7), c 15.273(8) Ǻ, β 92.44(4)°, Z4. The pair of quinol hydrogen atoms are both located on the one benzene ring as the title indicates.

scholarly journals Crystal structure of Tetraaqua(ethylenediamine)nickel(II) sulfate dihydrate and of Tetraaqua(2,2'-bipyridyl)nickel(II) sulfate dihydrate

1984 ◽  
Vol 37 (5) ◽  
pp. 921 ◽  
Author(s):  
PC Healy ◽  
JM Patrick ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Water Molecule ◽  
Single Crystal ◽  
Least Squares ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
Full Matrix ◽  
X Ray ◽  
Oxygen Atoms

The crystal structures of the title compounds, [Ni(OH2)4(en)] [SO4].2H2O, (1), and [Ni(OH2)4(bpy)]- [SO4].2H2O, (2), have been determined by single-crystal X-ray diffraction methods at 295 K, being refined by full matrix least-squares methods to residuals of 0.028,0.031 for 1852, 4323 independent 'observed' reflections respectively. Crystals of (1) are monoclinic, C2/c, a 9.459(4), b 12.192(7), c 12.294(3) �, β 119.84(4)�, Z 4. In the cation, Ni-N is 2.061(2) �; Ni-O (trans to O, N respectively) are 2.106(2), 2.063(2) �. Instead of being enlarged above 90� as predicted from repulsion theory, the angle between the pair of oxygen atoms trans to nitrogen is diminished, being 87 14(7)�. Crystals of (2) are triclinic, P1, a 11.476(5), b 9.351(5), c 7.793(4) �, α 77.63(4), β 83.52(3), γ87.40(4)�, Z 2. In the cation, Ni-N are both 2.063(2) �. Ni-O (trans to N, O respectively) are 2.060(2), 2.O42(2); 2.O80(2), 2�. The short Ni-O distance [2.042(2)�] is associated with the coordination of a trigonal water molecule.

The Alkaloids of Margaritaria indica (Euphorbiaceae). The Crystal Structure and Absolute Configuration of the Hydrobromide of (+)-15α-Methoxy-14,15-dihydrophyllochrysine

1990 ◽  
Vol 43 (2) ◽  
pp. 439 ◽  
Author(s):  
D Arbain ◽  
LT Byrne ◽  
JR Cannon ◽  
LM Engelhardt ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Absolute Configuration ◽  
Spectroscopic Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Least Squares Techniques

(-)-Phyllochrysine (1), (-)-securinine (2) and a new alkaloid (+)-15α-methoxy-14,15-dihydrophyllochrysine (3) have been isolated from both the bark and roots of Margaritaria indica ( Dalz .) G. L. Webster. The structure and absolute configuration of (3) follow from its spectroscopic properties and its synthesis from (-)- phyllochrysine (1) as well as from the crystal structure of its hydrobromide, obtained by X-ray diffraction. Diffractometer data at 295 K were refined by least-squares techniques to a residual of 0.053 (991 'observed' reflections). Crystals of 15α-methoxy-14,15-dihydrophyllochrysine hydrobromide are orthorhombic, P212121, a 14.324(3), b 14.194(3), c 7.240(2)Ǻ, Z 4.

The Conformation of Some 1,1,2,2-Tetraacylethanes in the Solid-State: Crystal-Structures of 1,1,2,2-Tetrabenzoylethane, 1,2-Diacetyl-1,2-Dibenzoylethane and 1,1,2,2-Tetraethoxycarbonylethane

1986 ◽  
Vol 39 (11) ◽  
pp. 1811 ◽  
Author(s):  
JR Cannon ◽  
VA Patrick ◽  
AH White
Keyword(s):  
Solid State ◽  
Least Squares ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
Keto Form ◽  
Carbon Bond ◽  
X Ray ◽  
Carbon Carbon Bond ◽  
Central Carbon ◽  
Least Squares Techniques

The crystal structures of 1,1,2,2-tetrabenzoylethane (3), 1,2-diacetyl- 1,2-dibenzoylethane (4) and 1,1,2,2-tetraethoxycarbonylethane (tetraethyl ethanetetracarboxylate ) (5) have been determined by X-ray diffraction from diffractometer data at 295 K and were refined by least-squares techniques to residuals of 0.050 (1077 'observed' reflections), 0.056 (3020) and 0.041 (480), respectively. Crystals of (3) are triclinic, Pī , Z 1, a 6.145(2), b 9.002(3), c 11.261(3) Ǻ; α 101.91(3), β 91.88(3), γ 105.94(3)°. Crystals of (4) are also triclinic, Pī , Z 2, a 17.119(5), b 7.210(1), c 7.175(2) Ǻ, α 89.59(2), β 72.92(2), γ 87.87(2)°. Crystals of (5) are tetragonal, P42/n, Z 4, a 17.748(6), c 5.515(1)Ǻ. In the solid state each compound exists in the keto form which adopts the antiperiplanar conformation about the central carbon-carbon bond.

Crystal structures of (Z)-O-β-D-xylopyranosyl(1 → 6)-→-D-glucopyranosyloxy-NNO-azoxymethane (Macrozamin) and 5-O-methyl-myo-inositol (Sequoyitol)

1980 ◽  
Vol 33 (10) ◽  
pp. 2229 ◽  
Author(s):  
JR Cannon ◽  
CL Raston ◽  
RF Toia ◽  
AH White
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
X Ray Diffraction ◽  
X Ray ◽  
Least Squares Techniques

Crystal structures of (Z)-O-β-D-xylopyranosyl(1→6)-β-D- glucopyranosyloxy-NNO-azoxymethane (macrozamin) (1) and 5-O-methy-myo-inositol (sequoyitol) (4)-both of which are constituents of Macrozamia riedlei (Fisch. ex Gaud.) C. A. Gardn.-have been determined by X-ray diffraction. Diffractometer data at 295 K were refined by least-squares techniques to residuals of 0.050 (1537 'observed' reflections) for macrozamin and 0.060 (1052) for sequoyitol. Crystals of macrozamin are monoclinic, P2I, a 8.315(3), b 10.410(4), c 10.423(5) Ǻ, β 106.42(3)°, Z 2. Crystals of sequoyitol are triclinic, Pī, a 4.780(5), b 6.502(6), c 14.668(10) Ǻ, α 96.43(7), β 94.20(8), γ 109.31(8)°, Z 2.

The X-Ray Crystal-Structure of (+/-)-Pandamarine, the Major Alkaloid of Pandanus-Amaryllifolius

1992 ◽  
Vol 45 (11) ◽  
pp. 1903 ◽  
Author(s):  
LT Byrne ◽  
BQ Guevara ◽  
WC Patalinghug ◽  
BV Recio ◽  
CR Ualat ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Diffraction Study ◽  
X Ray Diffraction ◽  
X Ray ◽  
Least Squares Techniques ◽  
Pandanus Amaryllifolius

The structure (2) of ( �)-pandamarine , the major alkaloid isolated from the leaves of Pandanus amaryllifolius Roxb., has been determined by an X-ray diffraction study. Diffractometer data at 295 K were refined by least-squares techniques to a residual of 0.049 2244 'observed' reflections). Crystals of (2) are triclinic, P1, a 13.077(2), b 9.857(5), c 7.214(2) �, α 106.91(3), β 96.22(2), γ 100.01(2)0, Z 2.

The structure of aqueous sodium hydroxide solutions: A combined solution x-ray diffraction and simulation study

2008 ◽  
Vol 128 (4) ◽  
pp. 044501 ◽  
Author(s):  
Tünde Megyes ◽  
Szabolcs Bálint ◽  
Tamás Grósz ◽  
Tamás Radnai ◽  
Imre Bakó ◽  
...  
Keyword(s):  
Sodium Hydroxide ◽  
Simulation Study ◽  
Aqueous Sodium Hydroxide ◽  
X Ray Diffraction ◽  
Aqueous Sodium ◽  
X Ray ◽  
Combined Solution

The crystal structures of 1,3-Diphenylpropane-1,2,3-trione, 1,4-Diphenylbutane-1,2,3,4-tetraone, 2,4-Dihydroxy-2,5-diphenylfuran-3(2H)-one and 3,3-Dihydroxy- 1,4-diphenylbutane-1,2,4-trione

1982 ◽  
Vol 35 (3) ◽  
pp. 543 ◽  
Author(s):  
RL Beddoes ◽  
JR Cannon ◽  
M Heller ◽  
OS Mills ◽  
VA Patrick ◽  
...  
Keyword(s):  
Least Squares ◽  
Crystal Structures ◽  
Carbonyl Groups ◽  
X Ray Diffraction ◽  
X Ray ◽  
Least Squares Techniques

As a contribution towards a study of the relative disposition of adjacent carbonyl groups in polycarbonyl compounds, the crystal structures of 1,3-diphenylpropane-1,2,3-trione (1), 1,4-diphenyl- butane-1,2,3,4-tetraone (3), 2,4-dihydroxy-2,5-diphenylfuran-3(2H)-one (benzoylformoin) (7) and 3,3-dihydroxy-1,4-diphenylbutane-1,2,4-trio (8) have been determined by X-ray diffraction from diffractometer data at 295 K and refined by least-squares techniques to residuals of 0.036 (942 'observed' reflections), 0.029 (979), 0.067 (941) and 0.045 (1661), respectively. Crystals of 1,3-diphenylpropane-1,2,3-trione are triclinic, P1, a 9.756(4), b 8.813(3), c 8.303(3) �,α 68.56(2), β 67.53(3), γ 89.11(3)�, Z 2. Crystals of 1,4-diphenylbutane-1,2,3,4-tetraone are monoclinic P21/c, a 10.641(2), b 8.381(2), c 14.710(4) �, β 91.70(2)�, Z 4. 2,4-Dihydroxy-2,5- diphenylfuran-3(2H)-one also forms monoclinic crystals, P21/c, a 5.741(4), b 9.276(7), c 24.31(2) �, β 106.26(5)�, Z 4. Crystals of 3,3-dihydroxy-1,4-diphenylbutane-1,2,4-trine are triclinic, P1, a 13.08(1), b 12.43(1), c 8.895(8) �, α 82.54(8), β 81.87(7), γ 78.61(7)�, Z 4.

Alkaloids of Templetonia retusa. Chemistry, Structure and Absolute Configuration of (-)-Templetine

1991 ◽  
Vol 44 (4) ◽  
pp. 509 ◽  
Author(s):  
JR Cannon ◽  
JR Williams ◽  
D Arbain ◽  
A Brossi ◽  
JF Blount ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Carbon Disulfide ◽  
Absolute Configuration ◽  
Perchloric Acid ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Absolute ◽  
Absolute Structure ◽  
Least Squares Techniques

(-)-Cytisine, (+)-lupanine, (-)-anagyrine, (�)-piptanthine and (-)-templetine have been isolated from Templetonia retusa (Vent.) R.Br. The absolute crystal structures of the trihydrochloride dihydrate and the isomorphous trihydrobromide dihydrate of (-)- templetine have both been determined by single-crystal X-ray diffraction; diffractometer data at 295 K were refined by least-squares techniques to residuals of 0.045 and 0.031, respectively, for 2351 and 1948 'observed' reflections. Crystals of the trihydrochloride are orthorhombic P212121, a 8.830(4), b 14.201(6), c 19.122(12)Ǻ, Z 4. Crystals of the trihydrobromide are isomorphous, a 9.081(3), b 14.578(2), c 19.197(11)Ǻ, Z 4. The absolute structure (1) of (-)- templetine has led to the absolute structure of its dehydrogenation product (-)- dehydropiptanthine perchlorate (7) which, in turn, has allowed the absolute structures of (-)- ormosanine (6), (+)- piptanthine (4) and (-)- panamine (9) to be defined. (-)- Templetine (1) reacts with formaldehyde to form homotempletine (12) and with carbon disulfide to yield the thiourea (13). Treatment of either (12) or (13) with W-1 Raney nickel followed by perchloric acid has yielded the diperchlorate (15). The X-ray crystal structure of the diperchlorate (15) has also been determined: diffractometer data at 295 K were refined by least-squares techniques to a residual of 0.056 (1312 'observed' reflections). Crystals of the diperchlorate (15) are orthorhombic, P212121, a 18.636(5), b 12.569(6), c 10.403(4)Ǻ, Z 4.

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