Hexamethyldisilathiane: Its Use in the Conversion of Aromatic and Heteroaromatic Azides to Amines

Synthesis of novel 2‐aminoimidazo[4,5‐b]pyridines, including the thieno analogue of the cooked‐food mutagen IFP

“…The azide 20 is isolable but light sensitive and thus preferable to suspend it in methanol immediately and treat it with 40% NH 4 SH [36] to form amine 21 [37,53]. The same procedure was used for the conversion of the 3-azido isomer 23 [52,53] to amine 24 [37,53] which was obtained in 92% overall yield from 22 [30].…”

“…The same procedure was used for the conversion of the 3-azido isomer 23 [52,53] to amine 24 [37,53] which was obtained in 92% overall yield from 22 [30]. The two orthoaminobenzothiophenecarbaldehydes 21 and 24 were treated with creatinine in BSA [30] to give 2 and 3 in almost quantitative yields (Scheme 5).…”

“…For the reduction of the azide 10 to amine 11 we found the use of commercial 40% ammonium sulfide (NH 4 SH) [36] advantageous compared to the highly poisonous hydrogen sulfide (H 2 S) gas [35] or the expensive bis(trimethylsilyl)sulfide [37]. For compound 11 we report the NMR-data obtained at 60 ºC in order to reduce the effect of the strong intramolecular hydrogen bonding, due to which both the formyl and the amino group gave two very broad signals each.…”

“…The substitution of the bromine was more efficient and hence it was our method of choice. By applying the same method on 19, amine 21 [37,53] was obtained in 91% overall yield via azide 20 [53]. …”

Hydrogen Processing by FeIII‐Exchanged Montmorillonite: A Unique Geochemical Protocol

“…The catalyst, used for four cycles, shows a slight decrease in activity after each run (Table 2, entry 7). These catalytic reactions effected by the cheap and readily available Fe III -mont are superior to the nonregenerable, stoichiometric hydride reagents or the expensive catalysts needed to reduce azo- [20,21] or cyanoarenes [22][23][24] under hydrogen pressure. Sim- [a] The calculation is given in the Supporting Information.…”