2-Oxabicyclo decan

It has also been known that the polymerization of some bicyclic lactam ethers, for example, 3-aza-10-oxabicyclo[4.3.1]decan-4-one 60 was accompanied by the cleavage of the ether bond55,56. ... 

I3C-NMR spectroscopic data of heteroanalogs of bicyclo[4.4.0]decane, collected prior to 1983, have been summarized25 77. Therefore, only a selection of subsequent studies is noted. H- and 13C-NMR spectra of diastereomeric substituted cis- and rraw-4-hydroxy-l-oxabicyclo[4.4.0]-decanes642, as well as H-NMR spectra of isomeric perhydrooxazolo[3,4-a]quinolines 3 and 3,3a,4,5-tetrahydro-1 //-oxazolo[3,4-a]quinolines 4, have been discussed 643. The 3H data of five diastereomeric 5-methyl-3-phenyl-2,4-dioxabicyclo[4.4.0]decanes have been reported644. 

Matsumoto and Tomioka examined chiral ketone 59 containing the l-aza-7-oxabicyclo[3.5.0]decane skeleton and its C2-symmetric analog 60 as catalysts in the asymmetric epoxidation of phenylcyclohexene and phenyldihydro-naphthalene (Scheme 23) in both cases, excellent yields of the oxiranes were obtained with good ee s <2002TL631>. 

One of the most complete descriptions of a stereochemical effect in mass spectrometry is the report of Turecek and Hanu (83T1499), where they discuss at length the stereoelectronic control of the loss of a hydrogen radical from the molecular ion radical of cyclic ethers under electron-impact conditions. In that paper, results are reported on 7-oxabicyclo[4.3.0]nonanes and 2-oxabicyclo [4.4.0] decanes. 

Table 15. Diastereoselective Synthesis of 9-Oxabicyclo[5.3.0]decane Derivatives...

Under a nitrogen atmosphere, a solution of 2.11 g benzophenone (11.6 mmol) and 3.83 g c/ -cyclooctene (34.8 mmol) in 300 mL petroleum ether at was irradiated in a Rayo-net photoreactor at 350 nm for 24 h. A white precipitate (350 mg) was formed during the irradiation, which was collected by filtration and identified as 1,1,2,2-tetraphenylethanediol (benzpinacol) by and C-NMR spectroscopy. Distillation of the solvent and most of the residual olefin at 50°C (10 mbar) afforded 3.66 g yellow oil, which contained both diastere-omeric oxetanes (cis/trans 40 60 by NMR spectroscopy). The crude product mixture (1.83 g) was purified by silica gel column chromatography with Et20/petroleum ether (1 10) as the eluent to afford 256 mg c/5-10,10-diphenyl-9-oxabicyclo[6.2.0]decane as a colorless oil, in a yield of 15%. In addition, 285 mg tran -10,10-diphenyl-9-oxabicyclo[6.2.0]decane was obtained as a colorless oil, in a yield of 17%. Further purification of each diastereomers was carried out by bulb-to-bulb distillation (Kugelrohr) at lOO C (0.03 mmHg). 

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