4- Substituted 3-bridged sulfonamides

Substituted-2-bridged Sulfonamides. This isomer is the easiest to synthesize due to the propensity of 3-substituted thiophenes to undergo electrophilic substitutions or directed metalations in the 2 position. Thus, the "Harmony" reverse isomer can be prepared from acid 32 via a directed metalation to the 2 position. The usual SO2... 

Sulfonamide groups incorporated in rotaxanes enable the construction of new topological assemblies provided with mechanically and covalently bonded subunits. Methylation of a [2]rotaxane containing a sulfonamide unit in the axle revealed that the substitution reaction is not sterically hindered by the macrocycle. Similar to the synthesis of the pretzelane 96, the two sulfonamide groups of rotaxane 80m were bridged with 95 to form 100 in 71% yield (Figure 39) [46]. The additional covalent bond converts the former [2]rotaxane into a [l]rotaxane and reduces the mobility of the wheel along the axle. Rotaxanes 80m and 100 are his-... 

The bridging of sulfonamide groups with diiodo compounds can also be applied to the intermolecular coupling of rotaxanes. When rotaxane 80e was treated with 95 under standard conditions, 76% of the wheel-bis[2]rotaxane 102 and 8% of the iodine-substituted rotaxane 101 were isolated (Figure 40) [46]. 101 is an excellent substrate for the synthesis of higher and unsymmetric rotaxane assemblies. 

The water-soluble reactive phthalocyanine dyes (see Section 2.8) yield brilliant turquoise and green shades not available from any other dye category. The most important reactive phthalocyanine dyes contain copper or nickel as their central atom they are substituted with sulfonic acid groups and also with reactive groups joined via sulfonamide bridges. An example is C.I. Reactive Blue 15, 74459 [12225-39-7] (23) ... 

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