Methane tritylation with

Typically, the resin is washed with a mixture of dichloro-methane and methanol (2 1 5 x 10 mL, shaking for 0.5 min each time), with a mixture of dichloromethane (9mL) and methylamine (1 mL, 30% solution in ethanol), with 1,2-dichlo-ropropane (10 mL) over night, with a mixture of dichloromethane (9 mL) and acetic acid (1 mL trityl resin-bound products should not be washed with diluted acetic acid), with a mixture of dichloromethane and methanol (2 1 3 x 10 mL, shaking for 0.5 min each time), and finally with dichloromethane (10 mL). Shorter washing protocols can lead to significant amounts of residual DBU in the final products. 

The reactivity of cellulose toward tri(p-toluenesulfonyl)methane chloride was recently examined [89]. The tosyl reagent is more reactive than trityl chloride, and the primary hydroxyl position exhibited 43 times more reactivity than the secondary hydroxyl groups. The products were used as intermediates in the synthesis of selectively modified cellulose derivatives [89]. As mentioned earlier, a high DS, organosol trimethylsilylcellulose has been prepared in DMAc/LiCl [10]. The condensation of polysaccharides with triphenyl-methyl (trityl) chloride proceeds generally with preference for the primary hydroxyl positions. The tritylation of cellulose occurs initially 58 times faster at the hydroxyl group at C6 than at either C2 or C3 [90]. 

Oxidation of ketone acetals and ethers.5 Ketones can be regenerated from the ethylene acetal derivatives by treatment with trityl Huoroborate in dry dichloro-methane (N2) at room temperature. Thus the reaction of trityl Huoroborate with cyclohexanone ethylene acetal results in cyclohexanone (80%) and triphenylmethane. The reaction thus involves hydride transfer to the triphenyl carbonium ions. Triethyl-oxonium Huoroborate can also be used but is somewhat less effective than trityl fluoro-borate. 

The conversion of 7 to 1 in high yields has previously been described by the Lilly group. The reaction of the diol with methane sulfonyl chloride was carried out in dichloromethane in the presence of triethylamine. The crude product was then recrystallized from a mixture of ethyl acetate and heptane. The reaction can also be carried out in ethyl acetate, eliminating the use of dichloromethane. Care should be exercised to remove all traces of acid from 1 since the trityl group can cleave in the presence of acids, causing the decomposition of the product. The yield of the product in this step was 85-90%. The chemical purity was >99% and ee was >99.5%. 

The salt is prepared1 in quantitative yield either by the reaction of triphenyl-methane with antimony pentachloride in carbon disulfide or by the reaction of trityl chloride and antimony pentachloride in carbon tetrachloride. 

Perlin, but a definite structure was not given. During the same work, both anomers of ethyl n-fructofuranoside were treated with chlorotriphenyl-methane. Only the /J-d anomer gave a crystalline 1,6-di-O-trityl derivative. The positions of the ether groups were determined by periodic acid oxidation, and, in both cases, one mole was consumed per mole. 

The facile conversion of C-nitromethyl- into aldehydo-groups with aqueous titanium (III) chloride has provided a convenient route to several C-formyl sugars, which can be isomerized to the thermodynamically favoured isomers with methan-olic sodium methoxide (Scheme 70). Conventional reactions have been used to obtain the 3-C-acetamidomethyl-3-deoxy-D-ribofuranose derivative (388) from l,2-0-isopropylidene-5-0-trityl-a-D-er> thro-pentofuranos-3-ulose, and the 6-benzoate (389) of 3-deoxy-l,2-0-isopropylidene-3-C-nitromethyl-a-D-allo-furanose has been converted, by a conventional chain-shortening procedure, into... 

Rapid advances are being made in the development and testing of new imidazole derivatives with antimycotic and other pharmacological properties. The drugs with antimycotic properties are Clotrimazole, a trityl imidazole derivative bis-phenyl(2-chlorophe-nyl-l-imidazolyl)methane Miconazole, a phenethyl imidazole l-[2,4 dichloro-j3-(2,4-dichloro-benzyloxy)phenethyl]imidazole E-conazole, also a phenethyl imidazole 1-[2,4-dichloro- 3-(p-chloro-benzyloxy) phen-ethyljimidazole. 

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