Cyclohexene assignments with explicit ambiguity for the overlapping allylic methylenes
. Details. 
Number ring positions through around the ring, with the double bond. These auxiliary ring-position labels are distinct from the printed carbon-signal numbers.
- : quaternary alkene carbon 4, attached to the OCH side chain.
- : alkene CH 8, proton E.
- : allylic CH, one of carbon signals 14/15; its protons are K and one of G/H/I.
- : methine 12, proton L, attached to the tertiary-alcohol carbon 10.
- : CH 17, protons J and M.
- : the other allylic CH 15/14, carrying the remaining two of G/H/I.
The HSQC pairs J and M with 17 and places L on 12. It also places K and one unresolved member of G/H/I on one of the closely spaced allylic carbons, with the other two G/H/I protons on the other. COSY connects the vinylic E to the adjacent allylic part and connects the methine L to its neighboring methylenes; HMBC links F to the substituted alkene end and the gem-dimethyl group to the methine end.
The printed overlap does not justify a unique assignment of every G/H/I letter or a forced 14-versus-15 assignment to those two ring positions. The drawing retains those alternatives explicitly. In the half-chair, L is pseudoaxial; the resolved large/small couplings are consistent with pseudoaxial/pseudoequatorial methylene partners, but exact axial letter labels within the overlapped group remain uncertain.
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