Nitrogen, Phosphorus, and Sulfur

Stereoisomers (Section 4.2) are compounds whose atoms are connected in the same order but with a different spatial arrangement. Among the kinds of stereoisomers we ve seen are enantiomers, diastereo-mers, and cis-trans isomers of cycloalkanes. Actually, cis-trans isomers are just a subclass of diastereomers because they are non-mirror-image stereoisomers  

Cis-trans diastereomers (substituents on same side or opposite side of double bond or ring) H / CH3 H3C / CH3 and 

Although the most common cause of chirality is the presence of four different substituents bonded to a tetrahedral atom, that atom doesn t necessarily have to be carbon. Nitrogen, phosphoms, and sulfur are all commonly encountered in organic molecules, and all can be chirality centers. We know, for instance, that trivalent nitrogen is tetrahedral, with its lone pair of electrons acting as the fourth substituent (Section 1.10). Is trivalent nitrogen chiral Does a compound such as ethylmethylamlne exist as a pair of enantiomers  

The answer is both yes and no. Yes in principle, but no in practice. Most trivalent nitrogen compounds imdergo a rapid umbrella-like inversion that 

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A similar situation occurs in trivalent phosphorus compounds, or phosphines, It turns out, though, that inversion at phosphorus is substantially slower than inversion at nitrogen, so stable chiral phosphines can be isolated. (R)- and (5)-methylpropylphenylphosphine, for example, are configurationally stable for several hours at 100 °C. WeTI see the importance of phosphine chirality in Section 26.7 in connection with the synthesis of chiral amino acids. 

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B. H. SvENSSON and R. Soderlund (eds.). Nitrogen, Phosphorus, and Sulfur-Global Biogeochemical Cycles, SCOPE Report, No. 7, Sweden 1976, 170 pp. also SCOPE Report No. 10, Wiley, New York, 1977, 220 pp, and SCOPE Newsletter 47, Jan. 1995, pp. 1-4. 

Describe the structures and properties of the nitrogen, phosphorus, and sulfur oxides. 

Feedbacks may be affected directly by atmospheric CO2, as in the case of possible CO2 fertilization of terrestrial production, or indirectly through the effects of atmospheric CO2 on climate. Furthermore, feedbacks between the carbon cycle and other anthropogenically altered biogeochemical cycles (e.g., nitrogen, phosphorus, and sulfur) may affect atmospheric CO2. If the creation or alteration of feedbacks have strong effects on the magnitudes of carbon cycle fluxes, then projections, made without consideration of these feedbacks and their potential for changing carbon cycle processes, will produce incorrect estimates of future concentrations of atmospheric CO2. 

Soderlund, R. and Svensson, B. H. (1976). The global nitrogen cycle. In "Nitrogen, Phosphorus and Sulfur - Global Cycles" (B. H. Svensson and R. Soderlund, eds), Ecol. Bull. No. 22, pp. 23-73, SCOPE. Swedish Natural Science Research Council, Stockholm. 

Schroder, D., Schwarz, H., Hrusak, J. and Pyykkd, P. (1998) Cationic gold(l) complexes of xenon and of ligands containing the donor atoms oxygen, nitrogen, phosphorus, and sulfur. Inorganic Chemistry, 37, 624—632. 

Where the target analyte contains heteroatoms such as nitrogen, phosphorus and sulfur, atom-selective detectors can provide an ideal detection method. A number of examples appear in the literature of the use of a detector called a thermal energy analyser (TEA) for the measurement of A-nitroso compounds [14-17] and aromatic nitro compounds [18]. This has also been used as an HPLC detector [19, 20], and a modified TEA has been reported to be useful for analysis of amines and other nitrogen-containing compounds [17]. Unfortunately, this technique appears not to have gained in popularity, since no reports have appeared in the literature for over two decades. 

Nitrogen, Phosphorus and Sulfur Atoms as Asymmetric Centers 232... 

The living substance is constituted by six major atomic elements entering the architecture of the biochemical molecules. They are carbon, which defines the organic chemistry (that is the chemistry of what s alive), hydrogen, oxygen, nitrogen, phosphorus, and sulfur. It is necessary to add to these five other elements of mainly ionic nature included in trace elements Na (Na ), Mg (Mg ), K (K ), Ca (Ca ), Cl (CF). These ions are essential to keep the balance of aqueous biological enviromnents whether they are in intra- or extracellular enviromnents. 

HO Interaction with N-, P-, and S-Containing Groups. A rather limited data set is available for quantification of the interaction of HO with nitrogen-, phosphorus-and sulfur-containing functional groups. The group rate constants for some func-... 

Granat, L. Rodhe, H. Hallberg, R. O. In Nitrogen. Phosphorus and Sulfur-Global Cycles. SCOPE Report 2, Ecol. Bull. Stockholm, 1976 22. 89. 

This section summarizes the chemical and physical properties which are shared in some degree by all of the nonmetallic elements, and the following sections briefly delineate the chemistry of several additional nonmetallic elements—carbon, silicon, nitrogen, phosphorus, and sulfur. A later section discusses the properties of the elements of the halogen family. 

Wollast, R. (1993) Interactions of carbon and nitrogen cycles in the coastal zone. In Interactions of Carbon, Nitrogen, Phosphorus, and Sulfur Biogeochemical cycles and Global Change (Wollast, R., Mackenzie, F.T., and Chou, L., eds.), pp. 195-210, Springer-Verlag, Berlin. 

Stribling, J. M., and Cornwell, J. C. (2001). Nitrogen, phosphorus, and sulfur dynamics in a low salinity marsh system dominated by Spartina alternijlora. Wetlands 21, 629—638. 

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