P-Nitrobenzenesulfonyl

The much-used sulfonylation by aromatic sulfonyl chlorides is illustrated by the conversion of quinazolin-4-amine into the sulfonamide (247) using p- nitrobenzenesulfonyl chloride at 60 °C (56JCS3509). 

The procedure given is applicable to many other aulfonyl chlorides as well (see Table I). Solid sulfonyl chlorides are added as such. When heavy frothing occurs in the reduction (e.g., with p-nitrobenzenesulfonyl chloride), addition of 50 ml. of chloroform to the reaction mixture will eliminate the foam without reducing the final yield. When the sulfonyl chlorides were prepared according to Meerwein and co-workers, it was found advantageous to use the crude, damp sulfonyl chlorides, since these are more easily reduced than the dried or recrystallized materials. 

Of course, new variants of the (N + C=C) approach continue to be reported. Muller and coworkers, who recently reviewed the field of rhodium(II)-catalyzed aziridinations with [N-(p-nitrobenzenesulfonyl)imino]phenyliodinane <96JP0341>, have explored the application of this technology to asymmetric synthesis. Thus, treatment of c/s-p-methylstyrene (141) with PhI=NNs and Pirrung s catalyst [Rh2 (-)(R)-bnp 4] in methylene chloride medium afforded the corresponding aziridine (142) in 75% yield and 73% ee <96TET1543>. 

The classic syntheses of the antibacterial sulfonamides involve reaction of the appropriate arylamine with an acid addition salt of p-amino-benzenesulfonyl chloride, or p-nitrobenzenesulfonyl chloride followed by reduction. Chemical interest largely resides in preparation of the corresponding arylamines. For the synthesis of sulfacytine (134), N-ethyl uracil (131) was converted to its thioamide (132) by reaction with phosphorous pentasulfide. The newly introduced sulfur is then displaced with ammonia in methanol to give 133. Standard reactions complete... 

Scheme 49. 1,3-Dipolar cycloaddition of p-nitrobenzenesulfonyl azide (219) onto dispirocy-clopropanated bicyclopropylidene 56 [140]...

The formation of ethoxycarbonylnitrene from the anion of iV-(ethoxycarbonyl) 0-(p-nitrobenzenesulfonyl)hydroxylamine 3n by elimination of p-nitrobenzenesulfonate was already reported (equation... 

Tardella s group have developed effective protocols for preparation of chiral a-amino-carbonyl compounds using a-A-(ethoxycarbonyl) 0-(p-nitrobenzenesulfonyl)hydroxyl-amine 3n in the presence or absence of a base . A chiral /S-ketocarboxamide carrying... 

Electron-donating substituents make the aromatic subsU ate more reactive than benzene and lead to o,/ -orientation, while electron-withdrawing substituents decrease the reactivity and give mostly m-orientation products. The detailed mechanism of the formation of the a complex has been studied by oxygen-18 labeling of the sulfonyl oxygen in p-nitrobenzenesulfonyl peroxide. The ionic mechanism for aromatic substitution by sulfonyl peroxides has been confirmed by carrying out the substitution reaction in the presence of redox catalysts such as copper and cobalt salts and aluminum chloride. Small differences in the rate of the products can be found in the presence or absence of these additives, and it has been concluded that the ionic mechanism accounts satisfactorily for these results. ... 

Nickel, dichloro [ethylenebis(dimethyl-phosphine)], 58, 133 Nickel, dichloro[ethj lenebis(diphenyl-phosphine)], 58,133 [Ni (-)-diop Cl2 ], (-)-diop=2,3-0-iso-propylidene-2,3-dihydroxy-l,4-bis(di-phenylphosphino)butane, 58, 133 Nickel, dichloro [ trimethylenebis(diphenyl-phosphine)], 58,133 NITRILES, alkylation of, 55, 91 NITRILES FROM KETONES, 58, 101 NITRILES, a vinyl, 55, 99, 101 p-Nitrobenzenesulfonyl cyanide, 57, 89 p-Nitrobenzyl alcohol, 57, 72 p-NITROBENZYL FLUORIDE, 57, 72 Nitro compounds, 56, 36 Nitronates, 56, 36... 

Reaction of p-nitrobenzenesulfonyl azide with alkylidenecycloalkanes 22-25187 does not yield isolable triazolines as expected, but the reaction products derived from alkenes 22 and 23 suggest a single triazoline intermediate, whereas in the case of tetrasubstituted derivative 24 both possible reaction modes are present,187 owing to weak double bond dissymmetry. Product analysis from 25 indicates some conflict between electronic and steric control in the addition, but provides evidence that electronic factors are much more important than steric effects in controlling regioselectivity.187 Reaction of the exocyclic olefins 22 and 23 appears to be controlled more by the interaction of the LUMO of the azide and the HOMO of the alkene.187 p-Nitrobenzenesulfonyl azide is reported to react with members of the novel... 

Similarly, spirotriazoline intermediates from the addition of p-nitrobenzenesulfonyl azide to exocyclic olefins 22 and 23 give a single ring-expanded sulfonimide (97),18 7 190-19 2 whereas those derived from 24 yield two sulfonimides, 97 from ring expansion and 98 from methyl migration.187 Four... 

The reagent is prepared by reaction of p-nitrobenzenesulfonyl chloride with 4-nitroimidazole (triethylamine). ... 

To a 3 L, three-neck flask equipped with a stirrer, thremometer, and condenser was charge 30.0 g (0.24 mole) of 3-azabicyclo[3.2.2]nonane, 44.3 g (0.2 mole) of p-nitrobenzenesulfonyl chloride and 2 L of water. The pH of the reaction mixture was adjusted to 14 with a 10% solution of sodium hydroxide the reaction mixture was then slowly heated to 75°C and heating stopped. 

The reaction mixture was cooled to 20°C and 44.0 g (71% of theory) of crude 3-(p-nitrobenzenesulfonyl)-3-azabicyclo[3.2.2]nonane was collected by filtration. 

The crude 3-(p-nitrobenzenesulfonyl)-3-azabicyclo[3.2.2]nonane (44.0 g, 0.14 mole), 5.0 g alcohol wet Raney nickel, and 400 ml methyl alcohol were charged to an autoclave and reduced at 70°C at 1000 p.s.i. hydrogen pressure until absorption of hydrogen had stopped. The crude reduced product was filtered hot to remove the Raney nickel catalyst. The filtrate was cooled to 20°C and the solid 3-(p-ammobenzenesulfonyl)-3-azabicyclo[3.2.2]nonane was collected by filtration (38.9 g 98% theory), melting point 149°-151°C. 

Guanidine hydrochloride Hydrogen chloride p-Nitrobenzenesulfonyl chloride... 

This starting material can be prepared as follows. 123 parts of finely powdered 6-amino-2,4-dimethylpyrimidine are suspended in 250 parts of dry pyridine and 222 parts of p-nitrobenzenesulfonyl chloride added at 50°C to 55°C. The whole is then warmed for 2 hours to 55°C. Water is added to the crystalline aggregate obtained, the precipitated bis-N-(p-nitrobenzenesulfonyl)-6-amino-2,4-dimethylpyrimidine filtered off by suction and washed with water. It is purified by recrystallizing from methyl ethyl ketone. On slowly heating it decomposes on rapidly heating it melts at about 210°C to 215°C with decomposition. 

Reactions of Ethyl Af-[(p-nitrobenzenesulfonyl)oxy]carbamate with Chiral Enamines and Enol Ethers... 

In contrast with the metallated 7V-[(arylsulfonyl)oxy]carbamates, it has been known since 1965 that ethyl N-[(p-nitrobenzenesulfonyl)oxy]carbamate 6e is a precursor of nitrene, thus a-elimination of p-nitrobenzensulfonate ion (NsO-) from the anion of ethyl Af-[(p-nitrobenzenesulfonyl)oxy]carbamate 6e leads at room temperature to the formation of (ethoxycarbonyl)nitrene 18 [12a] (Scheme 7). 

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