Triisopropylbenzenesulfonyl chlorides

Trimethylbenzenesulfonyl chloride has been shown21 to be much more selective for the monosulfonylation of a vicinal secondary diol (for example, methyl 4,6-O-benzylidene-a-D-gluco-pyranoside) than p-toluenesulfonyl chloride, and, apparently, 2,4,6-triisopropylbenzenesulfonyl chloride exhibits an even higher selectivity.22... 

In the early solution-phase synthesis of oligonucleotides, coupling of phosphate chesters was used. A mixed 3 -ester with one aryl substituent, usually o-chlorophenyl, was coupled with a deprotected 5 -OH. The coupling reagents used were sulfonyl halides, particularly 2,4,6-triisopropylbenzenesulfonyl chloride.153 The reactions proceed by... 

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... 

One variable that seems to influence the yields in the nucleophilic attack of hydroxyl groups on activated phosphate groups is the relative proportion of these two components in reaction mixtures. A 1 1 ratio of reactants may not be ideal54 if a considerable proportion of the nu-cleotidic component is converted into pyrophosphate, or if, as with activation by 2,4,6-triisopropylbenzenesulfonyl chloride (TPS) further reaction occurs after formation of one phosphoric diester linkage to... 

Thus, 3, 5 -di-0-(f-butyldimethylsilyl)thymidine (211) is sulfonylated by 2,4,6-triisopropylbenzenesulfonyl chloride (TIPS-CI) to furnish the 4-O-TlPS derivative 212 in 93% yield. Amination with 2-(methylam-ino)ethanol gives rise to 72% of 213 (87TL282I). 

Acetylation Acetic anhydride. N-Acetoxyphthalimide. 2- and 3-Acetoxypyridine. Acetyl chloride. N-Acetylimidazole. Boron trifluoride. Catalysts (see Acetic anhydride). Ketene. Magnesium. Methyl oxocarbonium hexafluoroantimonate. Perchloric acid. Phenyl acetate. Pyridine. Sodium acetate. Tetraelhylammonium acetate. p-Toluenesulfonic acid. Tri-n-hexylethyl ammonium hydroxide. 2,4,6-Triisopropylbenzenesulfonyl chloride. Trityl-sodium. Zinc chloride. 

GLYCEROPHOSPHOLIPIDS 2,4,6-Triisopropylbenzenesulfonyl chloride. GLYCIDIC ESTERS f-Butyl chloro-acetate. 

The 1,2-0-isopropylidene derivative 100, derived from L-sorbose, was also used for the synthesis of 1-deoxynojirimycin (2) (Scheme 19) It was prepared from L-sorbose by reaction with 2,2-dimethoxypropane in the presence of stannous chloride, followed by acid hydrolysis. Selective sulfonylation of the primary hydroxyl group with 2,4,6-triisopropylbenzenesulfonyl chloride (TIBSCl) in a 1 1 mixture of triethylamine and pyridine followed by nncleophilic displacement with azide ion in DMF afforded the 6-azido-... 

---