The structures of three racemic (tetrahydro-[1,3]dioxino[5,4-
An overview of magnetic circular dichroism (MCD) spectroscopy of π‐electron systems derived from a 4
- PAR ID:
- 10065696
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Physical Organic Chemistry
- Volume:
- 31
- Issue:
- 8
- ISSN:
- 0894-3230
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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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 ester1 at 173 K has triclinicP \overline{1} symmetry and both benzyl ether2 at 173 K and phenyl urethane3 have monoclinicP 21/c symmetry. 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. -
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