1.4- Diphenyl-butane

For the reaction of styrene with benzoylacetonitrile, 2-cyano- 1,4-diphenyl-butane-1,4-dione was isolated in 31% yield, while the reaction of 1,1-di-phenylethene with 2-(2-cyano-l-oxoethyl)-5-methylfuran gave 2-cyano-4,4-diphenylbutanolide in 83% yield and no 1,2-dioxanes were detected. Both exceptions are explained by the fact that the corresponding dioxane, once formed during the reaction, would be decomposed in acidic media (Scheme 16) [78,80,106]. 

The formation of intercalate structures have also been suggested for SPS co-crystals with3-carene (3,7,7-trimethylbicyclo[4.1.0]hept-3-ene) [23], anthracene [23,68], and a styrene dimer (1,4-diphenyl-butane) [24]. 

Die Hydroborierungsprodukte von cis- und trans-2,3-Diphenyl-buten-(2) lassen sich alkalisch direkt zu erythro- (69% d.Th.) bzw. threo-2,3-Diphenyl-butan (71% d.Th.) hy-drolysieren11 ... 

Eine wichtige Anwendung dieser Reaktion ist die Entschwefelung von Brennstoffen. Zur reduktiven Dimerisierung von oo-Brom-acetophenon zu 1,4-Dioxo-l,4-diphenyl-butan kann auch Pentacarbonyleisen eingesetzt werden (s. ds. Handb., Bd. VII/2b, S. 1877), obwohl in der Regel Zink/Kupfer verwendet wird. 

Aus Stilben wird mit tert.-Butylchlorid bei -2,3 V ein 3 2-Gemisch aus 3,3-Dimethyl-1,2-diphenyl-butan und 2-Phenyl-1-(4-tert.-butyl-phenyl)-dthan5 erhalten. 

R1 = R2 = CH3 2,3-Pyrrolidino-2,3-dimethyl-butan R1 = H R2 = C6Hs 2,3-Pyrrolidino-2,3-diphenyl-butan... 

Irradiation of styrenes in the presence of tertiary aliphatic amines resulted in the formation of adducts in fair to poor yield25. Excited styrene7 reacted with triethylamine to yield diastereomeric adducts 12, 1-phenylethane 16 and 2,3-diphenyl butane 1926 (equation 3). 

Dibenzoyl-furazan-2-oxid (r = r2 = co c(,hs) wird mil Zink/Eisessig bis zu l,4-Dioxo-l,4-diphenyl-butan reduziert es ist ungewiB, ob die Dioxim-Stufe durchlaufen wird215. 

Synthesis (Pohland, 1953 1955 1963 janssen and Karel (Janssen)1956 Sullivan et al., 1963) In the Grignard reaction of 3-dimethylamino-2-methyl-1-phenyl-propan-lone with benzylmagnesium chloride 4-dimethylamino-3-methyl-1,2-diphenyl-butan-2-ol is formed. The preferred product is the a-diastereomer(75 % a-form, 15 % p-form). The a-form crystallizes and the diastereomeric p-form remains in solution, because of its better solubility. Racemic resolution to obtain the analgetically (+) enantiomer can be achieved on the pure a-Grignard product via fractional crystallization of the salts with D-camphorsulfonic acid. Alternatively the resolution can be achieved by treating the racemic mannich product 3-dimethylamino-2-methyl-1-phenyl-propan-1-one with (-)-dibenzoyltartaric acid in acetone as solvent. 

ASYMMETRIC REDUCliON OF KETONES (S)-(—)-2-Amino-3-tHethyI-1,1 -diphenyl-butane- I -ol. (S)-4-Anilino-3-methylamino-I -butanol. 2,2-Dihyd(oxy-1,1 -binaphthyl. 

Tertiary aminocyclopropanes are stable towards basic conditions. In contrast, primary aminocyclopropanes undergo facile ring opening when treated with base. Thus, reaction of 1-amino-1-methyl-2,2-diphenylcyclopropane with aqueous sodium hydrogen carbonate or methanolic sodium hydroxide at room temperature results in the formation of 4,4-diphenyl-butan-2-one as the sole product (Table 13, entry 5). Formation of the nitrogen anion by deprotonation, followed by ring opening to form the benzhydryl anion, can account for the reaction course. 

Reactions of alkylbenzenes with other diones produced only 1,2-adducts even upon irradiation under irreversible conditions. Biacetyl and ethylbenzene gave 20> 50% of 1,2-adduct 101 plus radical dimers ((63) and 2,3-diphenyl butane), tetramethyltetrahydrofurandione (72) gave 15> high yield of adduct 102 with -xylene, tetramethyltetralindione (73)... 

Im Falle der Thermolyse (100°) iiberlagern sich heterolytische Spaltungsprozesse, wie aus den auf-tretenden Produkten zu entnehmen ist tert.-Butanol (17% d.Th.), Aceton, dessenDimethylaoetal (20% d.Th.), Methyl-isopropenyl-Sther (40% d.Th.), 2,3-Dimethyl-2,3-diphenyl-butan (20% d.Th.) und Succinimid (99% d.Th.). 

In a-Stellung besonders sperrig oder mehrfach substituierte Ketone konnen nicht re-duktiv aminiert werden2 z. B. 3-Oxo-2,2-diphenyl-butan bzw. 3-Oxo-2,2,3-triphenyl-propansaure-athyiester. 

A mixture of 6-dimethylamino-4,4-diphenyl-3-heptanone, KOH, and triethylene glycol refluxed 4 hrs. at a bath temp, of 220-230°, and the reaction product isolated as picrate -> 3-dimethylamino-l, 1-diphenyl-butane pierate. Y 90%. (E. L. May and E. Mosettig, J. Org. Chem. 13, 459 (1948).)... 

In other examples, biphotonic ionization of 2,3-dimethyl-2,3-diphenyl-butane (bicumene) in TFE gives the bicumene radical cation which undergoes carbon-carbon fragmentation to yield the cumyl cation and cumyl radical [87]. Photoinduced electron transfer from 2,2-dialkyldioxolanes to tetra-cyanoanthracene gives radical cations which fragment to yield dialkoxy carbocations and alkyl radicals [88]. Benzyl acetals were subjected to two-pho-... 

Diphenyl-3-methylbutane-l,2-diol, A"15.4 2-Methyl-3,4-diphenyl-butane-1,3-diol, A"44.7 4,4-Dimethyl-3-(l-naphthyl)butyric acid, A"45.14... 

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