4-methoxyphenyl 2- phenyl

Of these reactions only I and II-Z and the corresponding ee s work with high efficiency. The best phosphine available to us for these conversions was (fl,fl)-l,2-ethanediylbis-[(2-methoxyphenyl)-phenyl-phosphine](DiPAMP) (3). Since a number of variants of this molecule were readily available from a common, resolved intermediate, it seemed worthwhile to make a few of these with the hope of achieving marginal gains as well as improving our understanding of this remarkable catalysis. Table I shows a number of bisphosphines that were prepared for this study. 

Elix, J. A., and D. P. Murphy Annelated Furans. XVIII. The Photocyclization of 2-Methoxyphenyl Phenyl Ethers. Austral. J. Chem. 28, 1559 (1975). 

Ethane-l,2-diylbis (2-methoxyphenyl)(phenyl)phosphine the acronym is a derivative of the monophosphine, RAMP, phenylanisylmethylphosphine Di-iso-propyl tartrate 4-Dimethylaminopyridine... 

Early work in the field of asymmetric hydroboration employed norbornene as a simple unsaturated substrate. A range of chiral-chelating phosphine ligands were probed (DIOP (5), 2,2 -bis(diphenyl-phosphino)-l,l -binaphthyl (BINAP) (6), 2,3-bis(diphenylphosphino)butane (CHIRAPHOS) (7), 2,4-bis(diphenylphosphino)pentane (BDPP) (8), and l,2-(bis(o-methoxyphenyl)(phenyl)phos-phino)ethane) (DIPAMP) (9)) in combination with [Rh(COD)Cl]2 and catecholborane at room temperature (Scheme 8).45 General observations were that enantioselectivities increased as the temperature was lowered below ambient, but that variations of solvent (THF, benzene, or toluene) had little impact. 

Mit Aluminiumchlorid in Gegenwart von Wasser wurde Benzoin und COa gebildet. Analoge Ergebnisse wurden mit p-Methoxyphenyl-phenyl-triketon erhalten. 

Typical procedure. To a stirred solntion of Ph2TeCl2 (716 mg, 1.40 mmol), PdClj (25 mg, 0.14 mmol) and NaOMe (220 mg, 4.20 mmol) in CHjCN/MeOH (20 mL) under nitrogen atmosphere was added p-methoxyphenyl(phenyl)iodonium tetrafluoroborate (556 mg, 1.40 mmol) at room temperatnre. The reaction mixture was stirred at room temperature for 7 h. The reaction mixture was extracted with diethyl ether (3x20 mL). The organic layer was dried over anhydrous sodium sulphate and evaporated in vacuo. The crude product was separated by Si02 column chromatography (hexane, Rf=0.l7) to afford the conpled product (219 mg, 85%). 

The reaction of diphenylsilane with 4-methoxyphenyl tellurium trichloride in refluxing benzene did not form 4-methoxyphenyl phenyl tellurium dichloride, but rather bis 4-methoxyphenyl] tellurium dichloride in 85% yield4. 

HsCO- yteClj H5Ct-HgCl 4-methoxyphenyl phenyl 87 a 4... 

Allyl 4-methoxyphenyl phenyl telluronium bromide and bromine produced 4-methoxy-phenyl phenyl tellurium dibromide2. 

Methoxyphenyl Methyl Phenyl TeUnronium Iodide6 1.5 g (4.8 mmol) of 4-methoxyphenyl phenyl tellurium and 6.8 g (3 ml 48 mmol) of methyl iodide arc mixed and kept at 20° for 48 h. Diethyl ether is added to the mixture which is allowed to stand for 12 h. The mixture is then filtered and the solid dried yield 2.1 g (94%) m.p. 56°. 

To a solution of anthralin (5 mmol) dissolved in 80 ml toluene and 0.55 ml pyridine was added to 2-(4-(4 -methoxyphenyl)phenyl)acetyl chloride and the mixture heated to 80°C 3 hours, cooled, filtered, and concentrated. The product was purified by using CH2CI2. The purified fraction was concentrated and a small amount of hexane added to induce precipitation. 

To a solution of anthralin (4.4 mmol) dissolved in 50 ml CH2CI2 was added drop-wise at 0°C a solution of 2-(4-(4 methoxyphenyl)-phenyl)-l-chloro-l-methoxyethane (5.5 mmol) and the solution stirred 30 minutes. The mixture was thoroughly shaken with 2M HCl and the organic phase washed with brine, dried, purified by chromatography using CH2CI2, and the product isolated as in Step 1. 

Methoxyphenyl Phenyl Tellurium (Grignard Method) Phenyl magnesium bromide is prepared from 0.84 g (35 mmol) of magnesium and 5.5 g (35 mmol) of bromobenzene in 15 m/ of absolute diethyl ether under nitrogen and the resultant solution is cooled in an ice/watcr bath. 4.7 g (10 mmol) of bis [4-methoxyphenyl] ditellurium dissolved in 100 ml of absolute diethyl ether are added dropwise to the Grignard solution. Then 250 ml of petroleum ether (b.p. 30- 50°) are added to precipitate the tellurolate and the mixture is allowed to stand for 2 h. The precipitate is filtered off, the filtrate is mixed with aqueous ammonium chloride solution, the organic phase is separated, dried with sodium sulfate, and the solvent is evaporated. Methanol is added to the oily residue to crystallize the product yield 3.1 g (100%) m.p. 61° (from methanol). 

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