Jean Claude Daran

NEW PERHYDRODITHIAZINES, NMR AND X-RAY DIFFRACTION STUDIES

Abstract A series of new perhydro-1,3,5-dithiazines have been prepared: 1,1′-bis-[5-(perhydro-1,3,5-dithiazinyl)]dimethylsulfide 2, bis-[5-(perhydro-1,3,5-dithiazinyl)]methane 3, 1,2-bis-[5-(perhydro-1,3,5-dithiazinyl)]ethane 4, 1,3-bis-[5-(perhydro-1,3,5-dithiazinyl)]propane 5, 1,4-bis-[5-(perhydro-1,3,5-dithiazinyl)]butane 6, 1-[5-perhydro-1,3,5-dithiazinyl)]-3-[4-morpholinyl]propane 7, and 1,1′-[5-(perhydro-1,3,5-dithiazinyl)]-3,3′-[1,4-piperazinyl]propane 8. The structure of all compounds was studied by 1H and 13C NMR and molecular mechanics calculations. An X-ray diffraction study was performed on compounds 5-methyl-perhydro-1,3,5-dithiazine 1a and 5-tert-butyl-perhydro-1,3,5-dithiazine 1b and 5–7. In the X-ray diffraction studies and in the molecular mechanics calculation it was found that all the six-membered rings were in a chair conformation and that in all the studied perhydro-1,3,5-dithiazines the substituent at the nitrogen atom was in the axial position, even in spite of a strong steric hindr...

SYNTHESIS AND X-RAY DIFFRACTION STUDY OF 1,5-DITHIA-3,7-DIAZABICYCLO[3.3.1]NONANE AND ITS N-BORANE ADDUCTS

Abstract We report herein the synthesis of 1,5-dithia-3,7-diazabicyclo[3.3. 1]nonane. Its structural study in solution made by NMR, and its X-ray diffraction structure. Compound 1 forms mono-or di-adduct N-BH3 in the presence of 1.3 or 2.3 equivalents of BH3-THF, respectively.

HIGHLY REGIO- AND STEREOSELECTIVE FORMATION OF 2-HYDROXY-5,6-DIHYDRO-2H-1,4-OXAZINES. AN X-RAY AND 13C NMR STUDY

Abstract (−)-Norephedrine and (−)-norpseudoephedrine undergo condensation with a wide variety of 1,2-diketones to yield the corresponding 2-hydroxy-5,6-dihydro-2H-1,4-oxazines with high regio- and stereoselectivity. The X-ray structure analysis of five of the compounds studied shows that the stereochemistry at the newly formed stereogenic center is S in all cases.

Synthesis and coordination chemistry of tellurium alkynes

The reaction of (2,4,6-Me3C6H2)TeBr (I) with LiCue5fcCR (R = C6H5: IIa; R = SiMe3: IIb) gives excellent yields of the tellurium alkynes (2,4,6-Me3C6H2)TeCue5fcCR (R = C6H5: IIIa; R = SiMe3: IIIb). Compound IIIb reacts with octacarbonyl dicobalt (IV) to yield the side-on coordinated complex (2,4,6-Me3C6H2)Te[(η2-Cue5fcCSiMe3)CO2(CO)6] (V). The identity of compounds III and V have been established from analytical and spectroscopic (IR, 1H-, 13C-NMR) data and an X-ray diffraction study of V.