N -triphenylmethyl

Add with mixing to the fullerene solution 54 mg of either N-(triphenylmethyl)-5-oxazolidinone or the same amount of the methoxytrityl oxazolidinone. 

The monothioacetal is also stable to 12 N hydrochloric acid in acetone (used to remove an N-triphenylmethyl group) and to hydrazine hydrate in refluxing ethanol (used to cleave an N-phthaloyl group). It is cleaved by boron trifluoride etherate in acetic acid, silver nitrate in ethanol, and tiifluoroacetic acid. The monothioacetal is oxidized to a disulfide by thiocyanogen, (SCN)2.2... 

The same oxide reacts with tritylcyanamide to give a 78 % yield of N-triphenylmethyl-N -triphenylstannylcarbodiimide, and bis(tributylstannyl)oxide reacts with dicyandiamide to give a 98 % yield of bis(tributylstannyl)carbodiimide. ... 

Bifunctional systems form heterocyclic rings for example (194) yields (195). Photolysis of N-(triphenylmethyl)anilines results exclusively in C-N bond homolysis to give the trityl (< ) = 0.6-0.8) and anilino radicals." Reduction of the N-O bond cleaved intermediate (196) (formed on irradiation of 5-amino or 5-phenyl-1,2,4-oxadiazoles) by sodium hydrogen sulfide, thiols or thioamides yields the corresponding benzamidines (197). In contrast, in the presence of nucleophilic thioureas (199) or thiocarbamates (200), N-S bond formation occurs and subsequent elimination from the possible intermediate (201) yields the thiadia-zoles (198) or (202) respectively. ... 

II-Methyl-N -ohrysyl-thidhamstoff 12,1347. [4-Amino-ttipbanylaarbin]-rhodanid IS, 741. N-Triphenylmethyl-S-cyan-thiohydrozyl amin 15II21. 

C an benzy]idenaniino] mts4ure-akt..amylester 14 I 619, II 319. N-Triphenylmethyl-hydra in-N -carbon saure- thylester 15 H 266. [2.4-Dimethyl-butyTophenon] 6 azo 1>-naphthol-(2) 16 II93. 6-Acetamino-7-methyM.3 benzo-acridin. 

Schiff bases containing an imine moiety such as, for example, salicylideneani-hne and their derivatives are intensively investigated as model compounds for natural proton transfer systems [59, 60]. Depending on the solvent, there exists an equihbrium between the closed enol and the ds keto form. If the former is optically exdted, it undergoes ESIPT and transforms into the electronically excited cis keto form. The transfer was again found to be faster than 1 ps in the case of N-(triphenylmethyl)salicylidenimine [60] and even faster than 100fs for 4-methoxy-2,5-bis(phenyhminomethyl)phenol [59]. 

The 2,4,6-trimethylbenzyl ester has been prepared from an amino acid and the benzyl chloride (Et3N, DMF, 25°, 12 h, 60-80% yield) it is cleaved by acidic hydrolysis (CF COOH, 25°, 60 min, 60-90% yield 2 N HBr/HOAc, 25°, 60 min, 80-95% yield) and by hydrogenolysis. It is stable to methanolic hydrogen chloride used to remove A-o-nitrophenylsulfenyl groups or triphenylmethyl esters. ... 

The bulky triphenylmethyl group has been used to protect a variety of amines such as amino acids, penicillins, and cephalosporins. Esters of N-trityl a-amino acids are shielded from hydrolysis and require forcing conditions for cleavage. The a-proton s also shielded from deprotonation, which means that esters elsewhere in the molecule can be selectively deprotonated. 

Triphenylmethyl thioethers have been formed by reaction of the thiol with triphenylmethyl alcohol/anhydrous CF3COOH (85-90% yield) or with triphenyl-methyl chloride (75% yield). Glycosidic triphenylmethyl thioethers are prepared by displacement of the chloride with TrS N(Bu)4 (tetrabutylammonium triphenylmethanethiolate). ... 

The combination of carbon-centered radicals usually involves head-to-head (a,a ) coupling. Exceptions to this general rule occur where the free spin can be delocalized into a n-system. The classic example involves the triphenylmethyl radical (13) which combines to give exclusively the a-para coupling product (26), Scheme I.8).27 This chemistry is also seen in cross reactions of 13 with other tertiary radicals.146... 

The N+ relationship, as discussed above, is a systematization of experimental facts. The equation of Scheme 7-4 has been applied to nearly 800 rate constants of over 30 electrophiles with about 80 anionic, neutral, and even cationic nucleophiles covering a range of measured rate constants between 10-8 and 109s 1 (Ritchie, 1978). Only about a dozen rate constants deviated from the predicted values by more than a factor of 10, and about fifty by factors in the range 5-10. It is therefore, very likely that this correlation is not purely accidental. Other workers have shown it to be valid for other systems, e.g., for ferrocenyl-stabilized cations (Bunton et al., 1980), for coordinated cyclic 7r-hydrocarbons (Alovosus and Sweigart, 1985), and for selectivities of diarylcarbenes towards alkenes (Mayr, 1990 Mayr et al., 1990). On the other hand, McClelland et al. (1986) found that the N+ relationship is not applicable to additions of less stable triphenylmethyl cations. 

To create the free secondary amine group (N-H) fulleropyrrolidine, an amine-protected starting material can be used in the reaction (Cai et al., 2006). For instance, a trityl-oxazolidinone (using either triphenylmethyl- or better, 4-methoxytriphenylmethyl-protecting groups) can be reacted with C60 to yield the trityl-protected pyrrolidine (Figure 15.5). 

A bulky methacrylate, triphenylmethyl methacrylate (TrMA), is a unique monomer which gives an almost 100% isotactic polymer in anionic polymerization with n-butyllithium both in nonpolar and polar solvents. Moreover, even free-radical polymerization affords a highly isotactic polymer from this monomer.23 The isotactic specificity of TrMA polymerization is ascribed to the helical formation of the main chain. When TrMA is polymerized in toluene at —78°C... 

DIMETHYLAMINO-N-TRIPHENYLMETHYLPYRIDINIUM CHLORIDE (Pyridinium, 4-(dimethylamino)-1-(triphenylmethyl)-, chloride)... 

---