Alkane-2,6-diones

Alkane-2,6-diones give 3-alkylcyclohex-2-enones only by a kinetically controlled intramolecular cyclocondensation process promoted by a lithium dialk-ylamide in ether. ... 

Stereoselective hydrogenation ofl -diketones. Hydrogenation of 1,3-alkane-diones catalyzed by Ru2Cl4[(R)-l][N(C2H5)3] results in anf/-l,3-diols with high dias-tereoisomeric and enantiomeric excesses (equation I). Under the same conditions l-phenyl-l,3-butanedione (2) is reduced mainly to the (3-hydroxy ketone 3 in 98%... 

Compounds with two carbonyl moieties are named as alkane diones for example ... 

In general, peroxomonosulfates have fewer uses in organic chemistry than peroxodisulfates. However, the triple salt is used for oxidizing ketones (qv) to dioxiranes (7) (71,72), which in turn are useful oxidants in organic chemistry. Acetone in water is oxidized by triple salt to dimethyldioxirane, which in turn oxidizes alkenes to epoxides, polycycHc aromatic hydrocarbons to oxides and diones, amines to nitro compounds, sulfides to sulfoxides, phosphines to phosphine oxides, and alkanes to alcohols or carbonyl compounds. 

Preparation of 2-Cycloalkenones and Cycloalkane-1,3-diones BY Iron(III) Chloride-Induced Ring Opening of 1-Trimethyi,-siLYLOxY- AND 1,2-Bis(trimethylsilyloxy)bicyclo[w.1.0]alkanes... 

The bis(trimethylsiloxy)bicyclo[n.l.O]alkane 231 undergoes the FeCl3-induced ring expansion to the cycloalkane-1,3-dione 232. This method has been applied to the synthesis of macrocyclic tetraketones [128]. (Scheme 92)... 

Step 2 If there is one ketone group, replace the -e at the end of the name of the parent alkane with -one. If there is more than one ketone group, keep the -e suffix and add a suffix such as -dione or -trione. 

Reactions on similar compounds have been reported and in these cases only the cyclobutanones were isolated after in situ hydrolysis.26,30 For example, ll-oxatricyclo[6.3.0.01,6]undecan-2-one (6), 10-oxatricyclo[5.3.1.01,6]undecan-2-one (7) and (n + 10)-oxatricyclo[6.(n + 2).0.01,6]alkane-2,(n + 9)-dione (8) all gave good to excellent yields of the cyclobutanones after reaction with 3-chloroperoxybenzoic acid followed by hydrolysis. 

Reviews have appeared that in part cover recent advances in the ring-chain tautomerism of the nitrogen-containing derivatives of 1,3-dicarbonyl compounds (95ZOB705) of the reaction products of alkenals, alkenones, and alkane-1,3-diones with hydrazines and hydroxylamines (950PP519) and of other compounds [95H(41)1805 95H(41 )2057]. 

Various other [3 + 2] cycloadditions, affording chiral, anellated C6o derivatives with stereogenic centers in the addends are reported in literature. The products were generally obtained as racemates and resulted from reaction of buckminsterfullerene with species like 2,3-disubstituted 2//-azirincs (via nitrile ylides [under direct irradiation] or via 2-azaallenyl radical cations [sensitization by photoinduced electron transfer]),365 1-substituted 5-diazopentane-1,4-diones (via cyclic carbonyl ylides),366 7-alkylidene-2,3-diazabicyclo[2.2.1] hept-2-ene (via a diradicaloid trimethylenemethane derivative),367 1-benzylpy-razolidine-3-ones in the presence of aldehydes (via pyrazolidinium ylides),368 2-trifluoromethyl-2,5-dihydro-l,3-oxazol-5-ones (via nitrile ylides),369 nitro-alkanes in the presence of triethylamine and trimethylsilyl chloride (via N-silyloxynitrones),370 or dv-HOCH2 CH=C H C H 2 OCO 2 H( in the presence of... 

Conversion = (moles of alkane converted/total moles of alkane) x 100. Includes diols and diones. 

Dioxa-spiro 4.n]alkan 6-Oxo-E14a/1, 203 (Dion + Glykol)... 

Cyclohexan 1,3-Dioxo-2-methyl-2-(1-methyl-1-nitro-ethyl)- E19a, 746 (Dion A Nitro-alkan) Cyclopentan 2-Acetyl-2-(1-methyl-l-nitro-ethyl)-l-oxo- E19a, 1128 (R-X A R-M)... 

Reduction of 1,4-Diketones. Synthetic access to C2-symmetric 1,4-diols, useful building blocks for the preparation of chiral 2,5-disubstituted pyrrolidines and phospholanes, involves reduction of the parent 2-alkane-1,4-diones, or, even better, reduction of the related ( )-alk-2-ene-1,4-diones (11) (eq 7) or 2-alkyne-1,4-diones (12) (eq 8), followed by catalytic hydrogenation. ... 

Similar reactions with bis(trimethylsiloxy)bicyclo[4.1.0]alkanes afford cycloalkane-1,3 diones . ... 

The synthesis of cycloalkane-1,3-diones starts from bis(trimethylsilyloxy) bicyclo[n.l.O]alkanes and FeCl3, followed by treatment with Na02CCH3 in MeOH (Equation (lO)) 60... 

Similarly, alkane- and arenesulfonyl isocyanates gave 2-sulfonyl-2,3-dihydroisoindol-l-ones 11 with benzocyclopropene. 2,3-Dihydroisoindol-l-one was produced as a byproduct in 4% yield in the case of arenesulfonyl isocyanates. Cyclopropa[ ]naphthalene underwent addition to 4-phenyl-47/-l,2,4-triazole-3,5-dione at 20°C almost instantaneously to give an indazole 12 in 92% yield.Both reactions are believed to occur by electrophilic attack on the cyclo-proparene and may involve a zwittcrionic intermediate. When benzyne was generated from benzenediazonium-2-carboxylate in refluxing dioxane in the presence of cyclopropa[Z ]naph-thalenc, 5//-naphtho[2,5-a]indene was formed in 13% yield. 

Based on this premise, Crabtree and Dion" have successfully carried out indirect C-C bond cleavage of an unstrained alkane by an initial dehydrogenation reaction [Eq. (6.119)] ... 

Fig. 6 Chromatograms of extractions from virgin and recycled polyamide 6.6 after 25 h of thermo-oxidation at 100 °C. Identity of the peaks is 1 = cyclopentanone, 2 = 2-methylpyridine, 3 = pentanoic acid, 4 = butanamide, 5 = 2-ethylcyclopentanone, 6 = 2,4,6-trimethylpyridine, 7 = pentanamide, 8 = 3-(l-methylethyl)pyridine, 9 = 2-butylpyridine, 10 = N,N-hexamethylenebisformamide, 11 = 2-butylcyclopentanone, 12 = glutarimide, 13 = l-propyl-2,5-pyrrolidinedione, 14 = 2-pentylcyclopentanone, 15 = caprolactam, 16 = azepane-2,7-dione, 17 = 2-cyclopentyl-cyclopentanone, 18= l-butyl-2,5-pyrrolidinedione, 19 = l-pentyl-2,5-pyrrolidinedione, 20 = 2-butyl-3,5-dimethylethylpyridine, L1-L7 = linear C13-C17 alkanes and alkenes from lubricant, = silicone from septa used to seal vials. Reprinted from [65] with permission of John WUey Sons, Inc. John Wiley Sons, Inc (2002)...

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