Rotamer populations, substituted

Eliel et al. (72JA8587 76JA956) and Juaristi et al. (87JOC3806 90JOC33 92JA2157) studied the conformational behavior of 5-sulfur-substituted 1,3-dioxanes (see Table V) and discussed the results in terms of the rotamer population of the axial conformer in which steric, electrostatic, and stere-oelectronic effects are dominant. The sulfoxides place both the sulfinyl oxygen and the substituent outside the 1,3-dioxane ring in the sulfone, the position of the tBu substituent is similarly corroborated by an X-ray structure in the solid state. 

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