Oxirane, 2,2-dimethyl-3-phenyl

Phenacylmethyl(dimethyl)selenonium bromide is far more acidic than the selenonium salts presented above since deprotonation can be achieved with aqueous potassium hydroxide (Scheme 68). The resulting ylide is stable at room temperature and decomposes to 1,2,3-triphenacylcyclopropane on irradiation or heating (Scheme 68, a). It reacts with benzalacetophenone in a different manner from methylene(dimethyl)selenurane (Scheme 59, c) and provides, rather than the oxirane, l-phenyl-2,3-phenacy(cyclopropane in very high yield (Scheme 68, b). ... 

OXIRANES (Dimethylamino)phenyl-oxosulfonium methylide. Dimethyl-sulfonium methylide. (Dimethyl sulfoxide, derived reagent (b)). Methylene bromide-Lithium. Methylphenyl-N-p-tohienesulfonylsulfoximine. 

Dccyloxy-phenyl) 4-j[2-(3,3-Dimethyl-butyl)-oxiran-2-yl]-fliioro-methyl - ElOb, 89 (OH - F)... 

The (R) allene 121 was obtained with high anti stereoselectivity in the reaction of (i )-(—)-l-trifluoroacetoxy-l-phenyl-2-propyne (120) with PhZnCl. 2-Alkynyloxiranes react smoothly with alkynyl, alkenyl and arylzinc reagents. Reaction of 2-methyl-2-(l-propynyl)oxirane (122) with vinylzinc chloride (123) yields 2,4-dimethyl-2,3,5-hexatrien-l-ol (124) [31],... 

Dimethyl-(2-hydroxy-l -phenyl-ethoxy)- (2,4,6-trinitro-benzol-sulfonat) Ell, 371 (R2SO + subst. Oxiran)... 

Oxiran 2-Aziridino-3,3-dimethyl-2-phenyl- E14a/2, 382 (2-Brom-keton/Aziridin)... 

Oxiran 2-Methyl-3-(4-methyl phenyl)-2-trimethyl-silyl- E19d, 881 (H - Li/ + R-CHO) Propen 2-Methyl-l-phenyl-1-trimethylsilyloxy- E1S/1, 441 (Keton + R3Si —O —S02 —R) Silan Dimethyl-pentanoyl-phenyl-E19d, 570 (Acylierung) Spiro[4.4]nona-2,6-dien 6-Methyl-l -oxo-2(bzw. 3)-trimethylsiiyl-E19c, 221 (3-En-CO-Cl +... 

Potassium ert-butoxide, sodium hydride, butyllithium have all been used for this purpose. The alkyl(aryl)sulfanylcarbene (carbenoid) thus generated undergoes addition, often effectively, across the double bond of alkenes, enol ethers, ketene acetals and enamines. The use of chloromethyl phenyl sulfide, oxirane, tetraethylammonium bromide as a catalyst and an alkene gave phenylsulfanylcyclopropanes in rather low yield. For the synthesis of l,l-dimethyl-2-phenylsulfanylcyclopropane, see Houben-Weyl, Vol.4/3, p250 and of endoj exo-7-phenylsulfanylbicyclo[4.1.0]heptane, see Vol. E19b, pl691. 

Photolysis of (2-phenoxyphenyl)phenyldiazomethane (36) in cyclohexane at 10°C gave phenylcycloheptabenzofuran (37) via (2-phenoxyphenyl)phenylcarbene.The infrared spectrum of photo-chemically generated anthranylidene has been determined,and the dicarbene, (9,lO-dihydro-9,lO-o-benzeno-2,6-anthrylene)di(phenyl-methylene), has been shown by e.s.r. spectroscopy to have a quintet ground state.Products of photodecomposition 1,l-dimethyl-2-diazo-2-phenylethanol (38) in cyclohexane are the hydroxy ketone (39), the oxirane (40) and 3-phenylbutan-2-one (41), whereas reaction in methanol gave the methoxy alcohol (42) and the alkene (43).43... 

Demgegeniiber ergibt die Photolyse von 3,3-Dimethyl- (la R=CH3) oder von 3-Methyl-3-phenyl-2-benzoyl-oxiran (lb R=CSHS) 3-Hydroxy-4-oxo-2-viethyl-4-phe-nyl-buten-(l) (Ila 25% d.Th.) bzw. 3-Hydroxy-4-oxo-2,4-diphenyl-buten-(l) (lib 64% d.Th.)1- ... 

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