Septanose carbohydrates. I. Acid-catalysed reaction of D-glucose with acetone

1975 ◽  
Vol 28 (3) ◽  
pp. 525 ◽  
Author(s):  
JD Stevens
Keyword(s):  
Solid State ◽  
Acid Hydrolysis ◽  
X Ray ◽  
Catalysed Reaction ◽  
Hydrolysis Of ◽  
Derivatives Of

Two septanose derivatives of D-glucose, 1,2:3,4-di-O-isopropylidene-α-D-glucoseptanos(e4 a) and 2,3:4,5-di-O-isopropylidene-D-glucoseptanos(e5 a), have been isolated from the mixture of products formed by treating D-glucose with acidified acetone. Acid hydrolysis of (4a) yielded 1,2-O-isopropylidene- α-D-glucoseptanose which has been converted into a mixture of (4a) and a third D-glucoseptanose derivative, 1,2:4,5-di-O-isopropylidene-α-D-glucoseptanose (8a). Methylation of (5a) yielded the two D-glucoseptanoside derivatives, methyl 2,3:4,5-di-O-isopropylidene-α-D-glucoseptanoside and methyl 2,3:4,5-di-O-isopropylidene-β-D-glucoseptanosiwde, which have been selectively hydrolysed to give methyl α (and β-)-D-glucoseptanosides. Conformations of these various septanose compounds are proposed on the basis of n.m.r. parameters and these conformations are compared with those found in the solid state by X-ray analysis.

47,49Ti NMR in Metals, Inorganics, and Gels

2000 ◽  
Vol 55 (1-2) ◽  
pp. 291-297 ◽  
Author(s):  
T. J. Bastow
Keyword(s):  
Solid State ◽  
Titanium Oxide ◽  
Recent Progress ◽  
Titanium Isopropoxide ◽  
Metallic State ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrolysis Of ◽  
C Nmr

Some recent progress in solid state 47,49Ti NMR is described and reviewed. The metallic-state work described covers metals such as hep titanium, TiB2 , a number of intermetallics such as TiAl2 and TiAl3· The inorganic work covers the various titanium oxide based materials including the TiO2 polymorphs, anatase, rutile and brookite. The gel work covers the evolution of crystalline titania from gels formed by hydrolysis of titanium isopropoxide. Some complementary data from 17O and 13C NMR and powder X-ray diffraction is also included.

scholarly journals Bis(dicarbollide) Complexes of Transition Metals as a Platform for Molecular Switches. Study of Complexation of 8,8′-Bis(methylsulfanyl) Derivatives of Cobalt and Iron Bis(dicarbollides)

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5745
Author(s):  
Sergey A. Anufriev ◽  
Sergey V. Timofeev ◽  
Alexei A. Anisimov ◽  
Kyrill Yu. Suponitsky ◽  
Igor B. Sivaev
Keyword(s):  
Solid State ◽  
Transition Metal ◽  
Molecular Switches ◽  
X Ray Diffraction ◽  
Chelate Complexes ◽  
X Ray ◽  
Complexes Of Transition Metals ◽  
Silver Palladium ◽  
Solid State Structures ◽  
Derivatives Of

Complexation of the 8,8′-bis(methylsulfanyl) derivatives of cobalt and iron bis(dicarbollides) [8,8′-(MeS)2-3,3′-M(1,2-C2B9H10)2]− (M = Co, Fe) with copper, silver, palladium and rhodium leads to the formation of the corresponding chelate complexes, which is accompanied by a transition from the transoid to the cisoid conformation of the bis(dicarbollide) complex. This transition is reversible and can be used in design of coordination-driven molecular switches based on transition metal bis(dicarbollide) complexes. The solid-state structures of {(Ph3P)ClPd[8,8′- (MeS)2-3,3′-Co(1,2-C2B9H10)2-κ2-S,S′]} and {(COD)Rh[8,8′-(MeS)2-3,3′-Co(1,2-C2B9H10)2-κ2-S,S′]} were determined by single crystal X-ray diffraction.

Perchlorate and difluorophosphate coordination derivatives of rhenium carbonyl

1980 ◽  
Vol 33 (11) ◽  
pp. 2369 ◽  
Author(s):  
E Horn ◽  
MR Snow
Keyword(s):  
Heavy Atom ◽  
Coordination Geometry ◽  
X Ray Diffraction ◽  
Metal Centre ◽  
Triclinic Space Group ◽  
Full Matrix ◽  
X Ray ◽  
Rhenium Carbonyl ◽  
Hydrolysis Of ◽  
Derivatives Of

The complexes Re(CO)5ClO4, Re(CO)5PO2F2, L2(CO)3Re(OClO3) and L2(CO)3Re(PO2F2), where L2 = 2,2?-bipyridyl (bpy), have been synthesized by bromide abstraction reactions from the respective rhenium carbonyl bromide precursors. The complexes were characterized by infrared and mass spectroscopy. The crystal structure of (bpy)(CO)3Re(PO2F2) has been determined from X-ray diffraction data by the heavy-atom technique. The crystals are triclinic, space group Pī with a 8.620(3), b 15.912(5), c 6.466(3) Ǻ, α 102.08(8), β 83.29(8), γ 95.08(4) and Z 2. The structure has been refined by full-matrix least-squares from 2829 reflections to R = 0.084, Rw = 0.088. The coordination geometry about rhenium is that of a distorted octahedron. Difluorophosphate coordinates to the metal centre by one of its oxygen atoms. Formation of the difluorophosphate by hydrolysis of hexafluorophosphate was shown by 31P n.m.r. spectra.

1'-Derivatives of sucrose and their acid hydrolysis

1980 ◽  
Vol 33 (11) ◽  
pp. 2487 ◽  
Author(s):  
RD Guthrie ◽  
ID Jenkins ◽  
JJ Watters
Keyword(s):  
Acid Hydrolysis ◽  
Hydrolysis Of ◽  
Derivatives Of

Syntheses of 1'-chloro-1'-deoxy- and 1'-deoxy-sucrose are described. Several routes were investigated, the most successful being through 6,1',6'-tri-O-(2,4,6-trimethylbenzenesulfonyl)sucrose. Attempts to prepare 1'-deoxy-1'-fluorosucrose were unsuccessful. The rates of the acid-catalysed hydrolysis of 1'-chloro-1'-deoxysucrose and of 1'- deoxysucrose have been measured. These values are compared with that for sucrose itself. The mechanism of the hydrolyses is discussed.

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