Triphenylmethyl Trityl

FIGURE 7.27 Ester (IR 1825-1815 cm4) and amide IV-oxide (amide 3-oxide) (IR 1750-1730 cm4) forms of benzotriazole adducts.94 R = R O and R 0C(=0)-Xaa. Compounds with R = tBuO and PhCH2 are amide forms.97 The product from reaction of Trt-methionine and HOBt is the amide 3-oxide96 (Trt = trityl = triphenylmethyl). Note that the atoms bearing the oxygen atoms are numbered differently in the two compounds. 

NMO NMP Nu PPA PCC PDC phen Phth PPE PPTS Red-Al SEM Sia2BH TAS TBAF TBDMS TBDMS-C1 TBHP TCE TCNE TES Tf TFA TFAA THF THP TIPBS-C1 TIPS-C1 TMEDA TMS TMS-C1 TMS-CN Tol TosMIC TPP Tr Ts TTFA TTN N-methylmorpholine N-oxide jV-methyl-2-pyrrolidone nucleophile polyphosphoric acid pyridinium chlorochromate pyridinium dichromate 1,10-phenanthroline phthaloyl polyphosphate ester pyridinium p-toluenesulfonate sodium bis(methoxyethoxy)aluminum dihydride (3-trimethylsilylethoxy methyl disiamylborane tris(diethylamino)sulfonium tetra-n-butylammonium fluoride f-butyldimethylsilyl f-butyldimethylsilyl chloride f-butyl hydroperoxide 2,2,2-trichloroethanol tetracyanoethylene triethylsilyl triflyl (trifluoromethanesulfonyl) trifluoroacetic acid trifluoroacetic anhydride tetrahydrofuran tetrahydropyranyl 2,4,6-triisopropylbenzenesulfonyl chloride 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane tetramethylethylenediamine [ 1,2-bis(dimethylamino)ethane] trimethylsilyl trimethylsilyl chloride trimethylsilyl cyanide tolyl tosylmethyl isocyanide meso-tetraphenylporphyrin trityl (triphenylmethyl) tosyl (p-toluenesulfonyl) thallium trifluoroacetate thallium(III) nitrate... 

Azoisobutyronitrile Cyclopropylmethyl 3-exo Cyclisation A-endo Cyclisation Collidine DEPO Diethylphosphine oxide DPT Density functional theory DTBP Di-tert-butyl peroxide EPHP AT-Ethylpiperidine hypophosphite PCI Functional group interconversions EiMPA Hexamethylphosphoramide EDA Lithium diisopropylamide MAP 4-Methoxyacetophenone PTOC AT-Hydroxypyridine thione TMM Trimethylenemethane trityl Triphenylmethyl... 

Williams and Blann developed a route to cyclobutanols starting from carbohydrate-derived precursors [59]. The ketyl intermediates formed on treatment of precursors 35 with SmU in THF/HMPA underwent 4-exo-ketyl-olefin cyclisations to afford cyclobutanols 36 as isomer pairs (major isomer shown). Good yields were obtained for R = t-butyldimethylsilyl and trityl (triphenylmethyl), but for R = pivaloyl the reaction was diverted into an elimination pathway. 

Trityl (triphenylmethyl, Trt) esters are extremely labile toward acidic conditions and are selectively cleaved in the presence of ferf-butyl esters by treatment with AcOH at room temperature for a few minutes.The hydrochloride salts of amino acid trityl esters are hydrolyzed in aqueous and methanolic solutions. Amino acid trityl esters are obtained in satisfactory yields by treatment of the corresponding N -protected amino acid cesium salts with trityl chloride.t l... 

Many reactions that produce specific numbers and/or distributions of TV-substituents, or combinations of different TV-substituents, have been devised. The protecting groups boc (t-butyl-oxycarbonyl)104 and trityl (triphenylmethyl)105 are convenient since they can be removed under mild conditions. C-Substitution can alter the relative reactivity of nitrogen atoms by steric or inductive effects to determine substitution patterns (e.g., for the bis(l,2-cyclohexdiyl) cyclam (23), which preferentially bis-substitutes at the six and 16 sites).101 The presence of imine or amide functions also determine substitution patterns and the substituted imine or amide macrocycles can be reduced to the substituted cyclic amine. 

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