6-Hydroxy-6-methyl-2, 4-diphenyl

A solution of benzalacetone 2 (2.9 g, 0.02 mol) in dry acetone (50 ml) was added drop wise (30 min) at 0-10°C to a solution of amidine 1 (2.4 g, 0,02 mol) in dry acetone (50 ml) with constant magnetic stirring in a dry inert atmosphere (Scheme A.20). Following the addition, the mixture was stirred for another 30 min, after which the cooling bath was removed and the mixture was stirred at room temperature. The reaction was monitored by TLC. A white solid started to precipitate after the first hour. When the starting materials had disappeared almost completely (TLC), the white copious precipitate was filtered and washed with dry diethyl ether. The mother liquor was evaporated to dryness, the crude residue was triturated with a small amount of dry diethyl ether, and an additional portion of undissolved tetrahydropyrimidine was filtered off. The white solids were combined, dried and recrystallized. The yield of 6-hydroxy-6-methyl-2,4-diphenyl-1,4,5,6-tetrahydropyrimidine 3 was 82%. Melting point 80-81°C. 

A solution of 6-hydroxy-6-methyl-2,4-diphenyl-1,4,5,6-tetrahydropyrimidine 3 (5.3 g, 0.02 mol) in glacial acetic acid (15-20 ml) was heated at 80°C, for approximately 48 h. After cooling, ice (20 g) was added followed by dichloromethane (40 ml). A 25% aqueous solution of ammonia (20-25 ml) was added slowly with constant stirring until the mixture became basic. The dichloromethane layer was separated and the upper layer was extracted with dichloromethane (3 x 50 ml). The organic layers were combined, dried with magnesium sulfate and the solvent was evaporated in vacuo. The residue of 2-methyl-2,4-diphenyl-1,4-dihydropyrimidine 4 was recrystallized from ethyl acetate. Yield 98%. Melting point 145°C. 

CH3 1,2-diphenyl-4-butyl-4 (hydroxy-methyl)pyrozo-lidine-3,5 dione... 

CBS-catalyst1 01 B-methyl oxazaborolidine (prepared from (R)-2-(diphenyl-hydroxy-methyl)pyrrolidine and methyl boronic acid)[31], 1.85 g, 6.7mmol... 

Das aus 3,4-Bis-[a-hydroxy-methyl]-furazan zugangliche 3,4-Bis-[a-brom-benzyl]-furazati liefert mit Natriumsulfid 4,6-Diphenyl-4H, 6H-(thieno 3,4-e furu.zari). Letzteres wird durch Oxidation zum S-Oxid und anschliefiende Wasser-Abspaltung in 4,6-Diphenyl-(thieno( Sn) [3,4-c]fura-zan) iibergefiihrt270 ... 

Diphenyl-(2,2-diphenyl-2-hydroxy-]-methyl-elhyl)-phosphanoxid 84% Schmp. 260-262°... 

Chlor-2-hydroxy-propyloxy)-hydroxy- El, 315f. (Chlor-3-indolyl-methyl)-diphenyl- E2, 12 Chlormethyl-dibenzyl- E2, 218, 219 Chlormethyl-dimcthyl- E2, 63 Chlormethyl-diphenyl- XII/1, 155 Chlormethyl-hydroxy-... 

Chlor-(2,4,6-tri-tert.-butyl-phenyl)- El. 273 Cholesleryloxy-hydroxv- XII/2, 6 (2-Cyan-ethyl)-dibenzyl- XII/1, 154 (2-Cyan-ethyl)-dioctyl- XII/1, 154 (1-Cyan-l-methyl-ethyloxy)-hydroxy- XII/2, 7 (4-Cyan-phenyl)-diphenyl- E2, 64 (2-Cyan-propyl)-diphenyl- E2, 10 1-Cyclohexenyl-diphenyl- E2, 13, 52 l-(l-Cyclohexenyl-ethyl)-diphenyl- E2, 72 (2-Cyclohexenyl-hydroxy-methyl)-hydroxy-X1I/1, 299... 

Phosphanoxid Diphenyl-hydroxy-methyl- E2, 12 (Ar2P-Cl + CH20) Phosphinsanre... 

PHOSPHONIC ACID, 1-HYDROXY-l.l-ETHANEDIYL ESTER see HKS780 PHOSPHONIC ACID, (1-HYDROXYETHYLIDENE)BIS- see HKS780 PHOSPHONIC ACID, METHYL-, DIPHENYL ESTER see MDQ825... 

Methyl 2-(Diphenyl-hydroxy-methyl)-4-oxo-4-phenyl- 2134 Cyclopropane... 

Benzoyl-4-hydroxy-2-methoxybenzene sulfonic acid. See Benzophenone-4 2-Benzoyl-2-hydroxypropane. See 2-Hydroxy 2-methyl 1-phenyl 1-propanone Benzoyl methide. See Acetophenone 4-Benzoyl-4 -methyl diphenyl sulfide Synonyms BMDS... 

As in the examples described earlier, the alkenylations are usually performed in acidic solvents such as acetic and propionic acids, which limits coexisting functional groups in substrates. In contrast, the authors developed a reaction system, Pd(OAc)2/Cu(OAc)2/LiOAc/dimethylformamide (DMF), which is applicable to the reaction of thiophenes and furans possessing acid-sensitive substituents [42]. For example, the diphenyl(hydroxy)methyl function in diphenyl(2-thienyl)methanol is tolerable under the weakly basic conditions, as shown in Scheme 18.41. The function can be subsequently substituted by Pd-catalyzed arylation with aryl bromides via C-C bond cleavage to produce the corresponding 2-alkenyl-5-arylthiophenes. 

Preparation by reaction of dimethyl sulfate with 2,4-di-hydroxy-5-(diphenyl-methyl)desoxy-benzoin in the presence of potassium carbonate in refluxing acetone for 3 h (93%) [5274]. 

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