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Title: Structures of rac -2,4:3,5-dimethylene xylitol derivatives
The structures of three racemic (tetrahydro-[1,3]dioxino[5,4-d][1,3]dioxin-4-yl)methanol derivatives are reported, namely, 4-[(methylsulfonyloxy)methyl]-2,4,4a,6,8,8a-hexahydro-[1,3]dioxino[5,4-d][1,3]dioxine, C8H14O7S,1, 4-[(benzyloxy)methyl]-2,4,4a,6,8,8a-hexahydro-[1,3]dioxino[5,4-d][1,3]dioxine, C14H18O5,2, and 4-[(anilinocarbonyl)methyl]-2,4,4a,6,8,8a-hexahydro-[1,3]dioxino[5,4-d][1,3]dioxine, C14H17NO6,3. Mesylate ester1at 173 K has triclinicP\overline{1} symmetry and both benzyl ether2at 173 K and phenyl urethane3have monoclinicP21/csymmetry. These structures are of interest because of the conformation of thecis-fused tetraoxadecalin ring system. Thiscis-bicyclo[4.4.0]decane ring system,i.e. cis-decalin, can undergo conformational equilibration. In the two most stable conformers, both six-membered rings adopt a chair conformation. However, there are significant consequences in these two stable conformers, with heteroatom substitution at the 1,3,5,7-ring positions as described. Only one conformation, denoted as `concave' or `inside', is found in these crystal structures. This is consistent with previously reported structures of the 1,1-geminal dihydroxy aldehyde and tosylate analogs.  more » « less
Award ID(s):
2117549
PAR ID:
10557279
Author(s) / Creator(s):
;
Publisher / Repository:
IUCr
Date Published:
Journal Name:
Acta Crystallographica Section E Crystallographic Communications
Volume:
79
Issue:
9
ISSN:
2056-9890
Page Range / eLocation ID:
786 to 790
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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