Chemistry of hydrofluorenones. II. Synthesis from cyclohexyl benzoates

1976 ◽  
Vol 29 (12) ◽  
pp. 2683 ◽  
Author(s):  
KSN Ng ◽  
JL Roberts ◽  
PS Rutledge ◽  
MA Wilson ◽  
PD Woodgate
Keyword(s):  
Polyphosphoric Acid ◽  
Shift Reagent ◽  
Paramagnetic Shift ◽  
One Step

Synthetically useful substituted hexahydrofluoren-9-ones and hexahydrobenzofluoren-11-ones may be prepared in one step from cyclohexyl benzoates or naphthoates and polyphosphoric acid. When the hydrindanone ring junctions are unsubstituted the stereochemistry may be determined from the 1H N.M.R. spectra by decoupling the spectra after addition of a paramagnetic shift reagent.

scholarly journals Imaging Extracellular Lactate In Vitro and In Vivo Using CEST MRI and a Paramagnetic Shift Reagent

2017 ◽  
Vol 23 (8) ◽  
pp. 1752-1756 ◽  
Author(s):  
Lei Zhang ◽  
André F. Martins ◽  
Yuyan Mai ◽  
Piyu Zhao ◽  
Alexander M. Funk ◽  
...  
Keyword(s):  
Shift Reagent ◽  
Paramagnetic Shift ◽  
Cest Mri ◽  
Extracellular Lactate

Acetolytic cleavage of 2β,19-Epoxy-5α-cholestane involving a 1,2-Hydride shift to C2

1977 ◽  
Vol 30 (10) ◽  
pp. 2249 ◽  
Author(s):  
RE Gall ◽  
J Taylor
Keyword(s):  
Acetic Anhydride ◽  
Boron Trifluoride ◽  
Shift Reagent ◽  
Deuterium Exchange ◽  
Paramagnetic Shift ◽  
Nucleophilic Attack ◽  
Rearrangement Product ◽  
Hydride Shift ◽  
Carbonium Ion

Acetolytic cleavage of 2β,19-epoxy-5α-cholestane (1a) with boron trifluoride and acetic anhydride followed by hydrolysis gave the 2α,19- diol (2b), the only rearrangement product the 1α,19-diol (3b) and a mixture of olefins (4b). Deuterium exchange studies and the use of a paramagnetic shift reagent have shown that the reaction leading to the rearranged diol(3b) is not concerted and appears to involve an intermediate carbonium ion since hydride shift from both C 1 and C 3 occur. The formation of the 1α,19-diol (3b) as the only rearranged product can be rationalized as nucleophilic attack on the acetoxonium ion (8).

scholarly journals [Ln(DPA)3]3−Is a Convenient Paramagnetic Shift Reagent for Protein NMR Studies

2009 ◽  
Vol 131 (30) ◽  
pp. 10352-10353 ◽  
Author(s):  
Xun-Cheng Su ◽  
Haobo Liang ◽  
Karin V. Loscha ◽  
Gottfried Otting
Keyword(s):  
Protein Nmr ◽  
Shift Reagent ◽  
Paramagnetic Shift ◽  
Nmr Studies

Über die Struktur des Tris-[norbornyl-2] methanols / On the Structure of Tris-[norbornyl-2]methanol

1981 ◽  
Vol 36 (9) ◽  
pp. 1144-1146
Author(s):  
Klaus Roth
Keyword(s):  
Nmr Spectroscopy ◽  
Shift Reagent ◽  
Paramagnetic Shift

Abstract Tris[norbornyl-2]methanol The structure of the reaction product of the hydroboration oxidation of norbornene is determined by use of carbon-13 NMR spectroscopy. The conformers distribution of the resulting 1:3 mixture of the two stereoisomere 4 and 5 is analysed by addition of the paramagnetic shift reagent Eu(fod)3.

Synthesis, separation, and identification of 4-bromoadamantan-2-one stereoisomers

1980 ◽  
Vol 45 (10) ◽  
pp. 2670-2674 ◽  
Author(s):  
Luděk Vodička ◽  
Jan Tříska ◽  
Milan Hájek
Keyword(s):  
Ir Spectra ◽  
Hydrobromic Acid ◽  
Mass Spectra ◽  
Nmr Spectra ◽  
Dipole Moments ◽  
Hydroxylamine Hydrochloride ◽  
Shift Reagent ◽  
One Step ◽  
Elution Chromatography ◽  
The Eu

A one-step synthesis of mixture of stereoisomers of 4-bromoadamantan-2-one based on the reaction of adamantan-2-one with hydroxylamine hydrochloride in hydrobromic acid is described. The pure stereoisomers were isolated by elution chromatography on silica gel, and their NMR spectra with the Eu(FOD)3 shift reagent, mass spectra, IR spectra, and dipole moments were measured.

Sign in / Sign up

Export Citation Format

Share Document