Silicagel-supported H6P2W18O62.24H2O: a reusable catalyst to prepare diphenylmethyl (DPM) ethers

Abstract

In this work, we report an efficient and facile preparation of diphenylmethylethers (benzydryl ethers, DPM-ethers) from benzhydrol and alcohols or phenols. Wells-Dawson heteropolyacid (H 6 P 2 W 18 O 62 .24H 2 O), bulk or supported on silica showed catalytic activity for DPM-ethers preparation in toluene, at 60-80°C, in 0.5-1.5h. In these conditions twelve diphenylmethylethers of alcohols and phenol were obtained which excellent yields (78-96%). The heterogeneous reaction conditions provided a very simple, environmentally friendly, clean, economical and selective protocol, for the preparation of unsymmetrical ethers. The catalyst is easily recycled and reused without loss of the catalytic activity.

The Anodic Oxidation of 1,1-Diphenyl Ketones in the Presence of Nucleophiles

“…Compound F (RT = 14.3 minutes) was identified as 16b based on comparison of its fragmentation pattern and NMR spectra to those in the literature. 27 These peaks agree closely with those of the known compound.…”

“…The workup yielded 0.642 g of crude yellow oil, which was chromatographed over silica gel (95:5 hexanes:ethyl acetate) to yield 0.123 g (4.26 x 10 -4 mol) of a colorless oil which, from comparison of its 1 H NMR spectrum to that in the literature was identified to be mainly 16b. 27 GC yield = 50%, isolated yield = 19.0%. The following TIC indicates the endpoint of this reaction.…”

“…Compound A (RT = 8.0 minutes) was found to contain a peak of 121 in its mass fragmentation pattern not present elsewhere in the TIC, which was characteristic of phenethyl acetate (27). A sample of 27 was synthesized as described previously (See Results, Section C.(i).d) and was shown to match this peak in its retention time.…”

“…Compound B (RT = 7.9 minutes) was found to represent a mixture of phenethyl alcohol, supporting electrolyte, and an unidentified compound with a peak of 121 in its mass fragmentation pattern. Phenethyl acetate (27) was synthesized by the reaction of phenethyl alcohol and acetic anhydride in the presence of ptoluenesulfonic acid, and it was shown to match this peak in its retention time. Compound E (RT = 13.9 minutes) was identified to be benzhydryl benzyl ether (16e) based on comparison of its GC-MS data to that of a synthetic sample, prepared via the reaction of benzhydryl chloride with benzyl alcohol in the presence of silver tetrafluoroborate.…”

“…H NMR (CDCl 3 , 300MHz) δ(ppm): 7.35 (m, 10H), 2.48 (s, 3H).Phenethyl acetate(27): mL three-necked round-bottom flask charged with a stir bar was added 15 mL of acetic anhydride, 180 μL (1.449 x 10 -3 mol, 0.177 g) of phenethyl alcohol, and a spatula tip of catalytic p-toluenesulfonic acid. The reaction vessel was fitted with a reflux condenser and heated to 80 o C for twenty-four hours.…”