Stereochemical studies—76 saturated heterocycles—63 : synthesis of cis- and trans-n-methyl- and n-benzyl-4.5- and 5,6-tetramethylenetetrahydro-1,3-oxazines; an x-ray study of n-benzyl-cis-4,5-tetramethylenetetrahydro-1,-3-oxazinium- picrate☆☆☆

Add time:08/22/2019    Source:sciencedirect.com

- The corresponding cis- and trans-N-methyl- and N-benzyl-5,6- and 4,5-tetramethylenetetrahydro-l,3-oxazines (5a,b-8a,b)were synthesized from cis- and trans-N-methyl andN-benzyl-2- aminomethyl-1-cyclohexanols 1a,b,2a,b, from cis- and trans-N-methyl- and Nbenzyl -2-hydroxymethyl-1-cyclohexylamines(3a,b,4a,b) by reaction with formaldehyde. The aminoalcohols 1a,2a,3a,band 4a,b were prepared in considerably higher yields than in earlier procedures. NMR spectroscopy showed that the cis isomers of the synthesized oxazines were conformationally homogeneous in solution, and their preferred conformation (inside or outside) depended on the steric requirement of the groups attached to the anellation points, whereas a bulky C-2 substituent had no influence on the predominant conformation. The structure of N-benzyl-cis-4,5-tetramethylenetetrahydro-1,3-oxaziniumpicrate (7b). determined by X-ray diffraction analysis, was in agreement with the predominant N-outside conformation of the corresponding base, established by means of NMR spectroscopy.

We also recommend Trading Suppliers and Manufacturers of Methyl 1-(hydroxyMethyl)cyclohexanecarboxylate (cas 104654-66-2). Pls Click Website Link as below: cas 104654-66-2 suppliers

Prev:Asymmetric syntheses of (−)-methyl shikimate and (−)-5a-carba-β-d-gulopyranose from d-arabinose via Mukaiyama-type intramolecular aldolization
Next:Evaluation of the genotoxic activity of 2-nitroanthrafurans)