Disulfonamides

The product separates as a gum from which the supernatant liquid is decanted, and the gum is triturated with 250 cc of water in order to induce crystallization. The crude product thus obtained is recrystallized from 3,200 cc of boiling water and then from 40% aqueous isopropyl alcohol yielding 4,5-dichlorobenzene-1,3-disulfonamide as a white solid, MP 228.5° to 229.0°C. 

Chemical Name 4-chloro-N -methyl-N [tetrahydro-2-methyl-2-furanyl)methyl] -1,3-benzene-disulfonamide... 

B) Preparation of 4-Amino-2-Chloro-5-(Methylsulfamyl)Benzenesulfonamide The 5-sub-stituted-2,4-dlsulfamyl anilines may be prepared by procedures described in the literature, for example, the general procedures in Monatsch. Chem. vol. 48, p 87 (1927), which involves the treatment of a m-substituted aniline with from 10 to 20 parts by weight of chlorosulfonic acid followed by the gradual addition of from about 90 to 170 parts by weight of sodium chloride. The resultant mixture is heated at approximately 150°C for about 2 hours after which the reaction mixture is poured into water and the resultant 5-substituted aniline-2,4-disulfonyl chloride is filtered and is then treated with concentrated ammonium hydroxide or suitable amine by standard procedures to obtain the corresponding disulfonamide. 

S)-l-Phenyl-l-pentanol can be obtained, also in 98% ee, by addition of dibutylzinc to benzaldehyde in the presence of the disulfonamide/tetraisopropoxytitanium catalytic system26. 

In 2000, these workers described disulfonamide ligands derived from camphor, which could be easily prepared from chiral camphorsulfonyl chloride, and further successfully used in the enantioselective addition of ZnEt2 to... 

Camphor-derived disulfonamide ligand for additions of ZnEt2 aldehydes. 

In 2006, Wang et al. reported the synthesis of a new camphor-derived disulfonamide ligand based on L-tartaric acid that was employed in similar reactions to those described above, giving rise to enantioselectivities of up to 83% ee by using 5 mol% of catalyst loading (Scheme 3.43). ... 

The use of chiral C2-symmetric trifluoromethanesulfonamides derived from (i )-1,1 -binaphthyl-2,2 -diamine in similar reactions to those described above has led to the formation of the expected alcohols with enantioselectivities of 43-54% ees. Better enantioselectivities were observed by Paquette et al, resulting from the use of chiral C2-symmetric VERDI (verbenone dimers) disulfonamides derived from the dimerisation of (+ )-verbenone. Stereoselectivity levels ranging from 72 to 98% ee were observed, depending on the structural characteristics of the aldehyde (Scheme 3.45). ... 

Scheme 3.45 VERDI disulfonamide ligands for additions of ZnEt2 to aldehydes.

The preparation and the use of several C2-symmetric disulfonamides derived from 1,2-amino alcohols in the Ti-catalysed enantioselective addition of di-alkylzinc reagents to aldehydes was described by Yus et al., in 2002. The best... 

The disulfonamide library was tested in the TifO PrC-mcdiatcd addition of Et2Zn to aldehydes, a known process using the bis-trifluoromethylsulfonamide of 1,2-diaminocyclohexane.106 The tests were run in 30 different reaction vessels in parallel format. In order to increase throughput, each vessel was charged with four different aldehydes, and the enantioselectivities of the four reaction products were determined by conventional GC analysis of the crude mixtures. The idea of using a given catalyst to screen combinatorially the reactions of different substrates had previously been proposed but in a different context.45 In the present case each mixture required about one hour to be screened, which means that about 96 ee-determinations of products (52) (Scheme 11) could be performed per day.105 A total of 120 results were collected, the best ees being >90%. 

The standard synthesis of sydnones (Section 5.03.9.2) has benefited from the use of A,./V,iV, iV -tetrabromobenzene-1,3-disulfonamide (TBBDS) as an efficient promoter of the one-pot conversion of various iV-arylglycines to sydnone products <2006H(68)2343>. Conversion of A-arylglycines to sydnones was achieved in 85 to 95% yield using a combination of NaN02 and AczO in CH2C12 promoted by TBBDS, under mild and neutral conditions. 

Ukaji et al.117 reported an enantioselective cyclopropanation reaction in which moderate enantiomeric excess was obtained when a stoichiometric amount of diethyl tartrate was used as a chiral modifier. Takahashi et al.118 achieved better results using the C2-symmetric chiral disulfonamide 205 as the chiral ligand. 

Kavallieratos, K., Moyer, B. A., Attenuation of Hofmeister bias in ion-pair extraction by a disulfonamide anion host used in strikingly effective synergistic combination with a calix-crown Cs+ host, Chem. Commun., 1620-1621, 2001. 

A great advance in potency was achieved with the 1,2,4-benzothiadiazine 1,1-dioxide chlorothiazide (190), a cyclized aniline-2,4-disulfonamide which is a weaker inhibitor of carbonic anhydrase than acetazolamide, but a more powerful diuretic. The major contribution to diuretic activity in these compounds must come from some factor other than the inhibition of carbonic anhydrase since a ten-fold increase in activity was seen in the reduced compound hydrochlorothiazide (191 R1 = R2 = H, R3 = CI) which has only one-tenth of... 

Heat-resistant polyamide membranes containing pendant sulfonamide groups were also fabricated 91 93). Thus the membrane prepared from 2,2 -disulfonamide-4,4 -diaminodiphenyl ether-isophthaloyl chloride copolymer 34 gave the water permeation rate of 1700 1/m2 day and salt rejection of 65 %. The film with 50 p... 

Imido selenium compounds Se(NR)2, where R = Bu or Ts, were first noted to give allylic amination of alkenes and alkynes.232 Formally the NR function is inserted into the allylic C—H bond yielding the C—NHR moiety. Related reactivity was also found for the sulfur imides, S(NR)2.233 Reactions between 1,3-dienes and Se(NTs)2 give [4 + 2] adducts which, in the presence of TsNH2, react to generate 1,2-disulfonamides.234... 

Lewis acid-promoted asymmetric addition of dialkylzincs to aldehydes is also an acceptable procedure for the preparation of chiral secondary alcohol. Various chiral titanium complexes are highly enantioselective catalysts [4]. C2-Symmet-ric disulfonamide, chiral diol (TADDOL) derived from tartaric acid, and chiral thiophosphoramidate are efficient chiral ligands. C2-Symmetric chiral diol 10, readily prepared from 1-indene by Brown s asymmetric hydroboration, is also a good chiral source (Scheme 2) [17], Even a simple a-hydroxycarboxylic acid 11 can achieve a good enantioselectivity [18]. 

Starnes et al. [34] synthesized a disulfonamide porphyrin receptor 37. Anion binding was detected by the perturbations of the porphyrin Soret and Q bands. The Soret band of 37 at 422 nm showed a red shift upon addition of anions in CH2C12 and isosbestic points were observed. Compound 37 was able to bind F via hydrogen bonding from sulfonamide NH protons in a 2 1 anion-to-ligand ratio with lCal=255,000 M"1 and iCa2= 1,700 M"1. 

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