1146980-46-2Relevant academic research and scientific papers
Trifluoroacetic acid-mediated facile transformation of 2-C-hydroxymethyl-d-glycals to chiral pyrano[2,3-b]benzopyrans
Santhi, Meenakshisundaram,Balasubramanian, Kalpattu K,Bhagavathy, Shanmugasundaram
, p. 521 - 525 (2009)
Treatment of 2-C-hydroxymethyl-d-glycals with phenols in trifluoroacetic acid at ambient temperature leads to an extremely facile transformation affording chiral pyrano[2,3-b]benzopyrans in high yields.
Montmorillonite K-10 clay-catalyzed Ferrier rearrangement of 2-C-hydroxymethyl-D-glycals, 3,4,6-tri-O-alkyl-D-glycals, and 3,4-(dihydro-2H-pyran-5-yl)methanol: A few unexpected domino transformations
Kumaran, Elumalai,Santhi, Meenakshisundaram,Balasubramanian, Kalpattu K.,Bhagavathy, Shanmugasundaram
experimental part, p. 1654 - 1661 (2011/11/06)
Montmorillonite K-10 clay-catalyzed substitution reactions of 3,4,6-tri-O-alkyl-2-C-hydroxymethyl-Dglycals, 3,4,6-tri-O-acetyl-D-glycals, 3,4,6-tri-O-alkyl-D-glycals, and 3,4-(dihydro-2H-pyran-5-yl)methanol with a few alcohols and phenols are described. The reactions of 2-C-hydroxymethyl-D-glycals with phenols were similar to those of 2-C-acetoxymethyl-D-glycals and afforded pyrano[2,3-b]benzopyrans. This montmorillonite K-10 clay-catalyzed transformation is facile both under ambient (Method 1) and microwave conditions (Method 2). Ferrier rearrangement of 3,4-(dihydro-2H-pyran-5-yl)methanol with p-cresol, 2,6-xylenol, and ethanol led to totally unexpected transformations. Reaction of 2-C-hydroxymethyl- D-galactal with 2,6-dimethylphenol in the presence of montmorillonite K-10 led to a novel domino transformation affording 4-(5',6'-dihydro-4H-pyran-3'-ylmethyl)-2,6-dimethylphenol. In contrast, 3,4,6-tri-O-acetyl-D-glucal furnished the Ferrier rearrangement product, 2,6-dimethylphenyl 4,6-di-Oacetyl- 2,3-dideoxy-α-D-erythro-hex-2- enopyranoside. Also, isomerization of 3,4,6-tri-O-alkyl-D-glycals to products of allylic rearrangement, 2,3-unsaturated-O-glycosides in good yields is reported.
Tailor-made chiral pyranopyrans based on glucose and galactose and studies on self-assembly of some crystals and low molecular weight organogel (LMOG)
Roy, Soumik,Chakraborty, Arijit,Chattopadhyay, Basab,Bhattacharya, Abir,Mukherjee, Alok K.,Ghosh, Rina
experimental part, p. 8512 - 8521 (2010/11/16)
InCl3 catalyzed reactions of 2-C-acetoxymethylglycal derivatives with different phenolic compounds resulted in the formation of sugar based pyranoarenopyrans in good yields and moderate to excellent diastereoselectivity in favor of 10aR- or 12aR- or 14aR-products. One of the synthesized compounds, viz. (2R,3R,12aR)-2,3,5,12a-tetrahydro-2-methoxymethyl-3-methoxypyrano[2,3-b] naphtho[1,2-e]pyran gelated polar solvents like MeOH, EtOH and non-polar solvents like pentane, hexane, heptane, octane, pet. ether, etc. The SEM picture of the corresponding hexane xerogel exhibited a rare type of microtubular gel assembly, whereas the SEM pictures of MeOH and pet. ether xerogels showed different types of three-dimensional network. Study of the MeOH gel by Fluorescence spectroscopy, 1H NMR and X-ray powder diffraction analysis indicated that the supramolecular assembly in the MeOH gel can be attributed to π-stacking. The crystal packing of (2R,3R,10aR)-3,10a-dihydro- 2-methoxymethyl-3-methoxy-7-methyl-2H,5H-pyrano[2,3-b][1]benzopyran, a benzopyran analogue of the above organogelator was stabilized by C-H?O and C-H?π hydrogen bonds forming one-dimensional columns parallel to the [001] direction, whereas the corresponding benzopyran 3-epimer showed only C-H?O hydrogen bonds among the molecules.
