3-(2-Furylmethyl-ene)-1,5-dioxaspiro-[5.5]undecane-2,4-dione
Abstract:
In the title mol-ecule, C(14)H(14)O(5), the 1,3-dioxane ring is in an envelope conformation with the ring C atom common to the cyclo-hexane ring forming the flap. The other five atoms of the 1,3-dioxane ring are essentially planar [maximum deviation from the least-squares plane = 0.041 (3) Å] and form a dihedral angle of 13.75 (2)° with the furan ring. In the crystal structure, weak inter-molecular C-H⋯O hydrogen bonds form extended chains along [101].
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Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the double...
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