Sulfenamides amides

TABLE 9.26 Effect of Sulfenamide Amide Fragment Basicity (p/f j) on ... 

Pyridinethiol, Et3N, CH2CI2, 95% yield. The methylthioamide group is stable to 2.5 N NaOH, THF, H2O and to 10% H2SO4, MeOH, H20. The section on sulfenamides should be consulted for a related approach to nitrogen protection. Some of the derivatives presented there may also be applicable to amides. 

The section on sulfenamides should be consulted for a related approach to nitrogen protection. Some of the derivatives presented there may also be applicable to amides. 

Tris(organoamino)boranes have been utilized to prepare, in reasonable yields,4,5 mono- and dihalo(organoamino)boranes which are often difficult to obtain by direct amination of the boron trihalides. Carboxylic acids, 1,3-diketones, ketones, and /3-ketoesters have been converted into carboxamides, enamino-ketones, enamines, and j -enamino-amides, respectively, by reaction with an appropriate tris(organoamino)borane under very mild conditions.6 Sulfenamides (R2NSC6H5) have also been prepared in high yield from selected tris(organoamino)boranes and sulfenic esters under relatively mild conditions.7... 

The reaction of alkenes with the stable, crystalline, and easily available Y-(4-nitrophenyl)benzene-sulfenamide in acetonitrile in the presence of boron trifluoride at 20 °C afforded mainly //-phen-ylthio amidines 7, together with /3-phenylthio amines 6 and /3-phenylthio amides 8122. However, by working at 100 °C in the presence of a small amount of water the /3-phenylthio amides 8 were the main products. For cyclohexene, high selectivity for tram addition (consistent with a mechanism involving the intermediacy of episulfonium ion) to cyclohexene is observed the reaction was limited to cyclohexene and terminal alkenes other 1,2-disubstituted alkenes were not used. 

Carboxylic acid amides from sulfenamides NSAr NCOR... 

A vulcanizing system for NBRs had the following composition, phr stearic acid, 2.0 Sulfenamide Ts (7V-cyclohexylbenzothiazole-2-sulfen-amide), 1.5 zinc oxide, 5.0 and sulfur, 0.75. EPDM of the Royalen brand, the DSM and domestic EPDM was vulcanized with supported Peroximon F-40 taken in an amount of 5.5 phr. Each rubber was mixed with its vulcanizing system by roll milling at 40-60 °C for 15 min. Then, a rubber blend was prepared under the same conditions. The blends were vulcanized at 170 °C within 15 min. 

Sulfenamides 59 in place of thiols can lead to the regioselective and stereoselective formation of 3-alkylthio-a, 3-unsaturated amides 60 under Pd-catalyzed carbonylative thiocarbonylations (Scheme 46.10). The use of monothiocarbonates 62 can also lead to the stereoselective... 

Exhaustive acylation of a series of secondary amides has also been performed with B0C2O in dry acetonitrile at ambient temperature using DMAP as catalyst. The method has some steric limitations. For instance, it is retarded in the case of the ortho-substituted benzamides. The reaction has been extended to the acylation of carbamates and other amide type functions sulfonamides, sulfenamides, and phosphinamides. (J-Lactams are also A -protected in good yields (eq 17). ... 

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