Nitrogen, influence

Substituents on imino nitrogen influence both reactivity and enantioselectivity in hydrogenation of imino compounds. Figure 1.32 shows two successful examples. An f-BINAPHANE-Ir complex effects asymmetric hydrogenation of A-aryl aromatic imines.On the other hand, an Et-DuPHOS-Rh complex (see Figure 1.2) is effective for hydrogenation of A-acyUiydrazones. ... 

Nitro substituents and heterocyclic nitrogen influence not only the yield of fluorodediazoniation but also the rate of decomposition which, in these cases, is too high to perform the reaction on a multigram scale. Some explosions have been reported. Thus, the decomposition of nitro-substituted or heterocyclic diazonium tetrafluoroborates is usually controlled by three-to fivefold dilution of these substrates in inert solids, such as acid-washed sand,113 218 Kiesel-guhr,3 sodium carbonate,3 barium sulfate,217 sodium fluoride,216 or sodium tetrafluoroborate.3 This modified technique has been generalized to the decomposition of all kinds of diazonium tetrafluoroborates under safe conditions, even on rather large scales. 

Generally, substituents located on saturated groups attached to nitrogen influence base strengths through their inductive effects in the same way that these substituents influence the strengths of carboxylic acids (see Section 18-2). 

DelBene, J.E. and Bartlett, R.J., N-N spin-spin coupling constants [2hJ(15N-15N)] across N-H N hydrogen bonds in neutral complexes to what extent does the bonding at the nitrogens influence 2hJN-N communication, J. Am. Chem. Soc., 122, 10480 2000. 

Radical alkylations of pyridines and quinolines preferentially occur at positions 2 and 4. Protonation of the ring nitrogen influences the regioselectivity by favoring C-4 substitution. 

Recently detected couplings across hydrogen bonds have become an object of great interest. Theoretical studies on this topic have been performed by Del Bene et al., who analysed the parameters which determine N-N and 0-0 couplings, across X-H - X hydrogen bonds,and considered to what extent the bonding at the nitrogens influences Comprehensive ab... 

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