91546-55-3Relevant academic research and scientific papers
SYNTHESIS OF 3-METHYLENE-1-OXA-8-HETERASPIRODECAN-2-ONES AND 1-OXA-8-HETERASPIRODECAN-2-ONES. NOVEL FORMATION AND CRYSTAL STRUCTURE OF 3--1-OXA-8-THIASPIRODECAN-2-ONE
Satyamurthy, Nagichettiar,Berlin, K. Darrell,Powell, Douglas R.,Helm, Dick van der
, p. 137 - 154 (2007/10/02)
A series of new 3-methylene-1-oxa-8-heteraspirodecan-2-ones have been prepared as the first members of the family.Reaction of 1-oxa-6-heteraspirooctanes with diethyl malonate, followed by hydrolysis, gave 3-carboxy-1-oxa-8-heteraspirodecan-2-ones.The carboxy lactone, upon treatment with diethylamine and formaldehyde followed by sodium acetate and acetic acid, produced α-methyl-eneheteraspiro lactones in good yields and in high purity.Moreover, the carboxy lactones could be decarboxylated smoothly to give 1-oxa-8-heteraspirodecan-2-ones in good yields.The present method appears to be superior to the widely used Reformatsky reaction since only low yields of the required lactones could be obtained when applied in the work reported herein.An investigation of dilithiated acetic acid as a co-reactant with spiro epoxides of heteracyclohexyl systems was undertaken but rather than the expected γ-lactones, unusual γ-hydroxylactones were obtained.Apparently, the anionic behavior of the dilithiated acetic acid caused the condensation to occur.All lactone systems were characterized via IR, 1H NMR and 13C NMR analysis and mass spectral data.A single crystal analysis by X-ray diffraction of 3--1-oxa-8-thiaspirodecane-2-one l2l2l, Z=4, a=5.916(2), b=11.585(3), c=21.986(5) Angstroem, T=138 K> was completed.Least-squares refinement converged to R=0.045 for 1319 diffractometer data.Both thiacyclohexyl rings are in the chair conformation and have C-O bonds which are axial.The sulfur ring with the hydroxyl group is orientationally disordered.This is the first example of such a fused heterocycle in which a structure of the crystal has been reported.
