Nitrogen carbon-phosphorus bonds

The decomposition of nitrilotrimethylenetriphosphonic acid in acid solution has been studied. At 125-175° and pH 1.5, carbon-phosphorus bond cleavage occurs, but in 5M HC1 aq. carbon-nitrogen fission becomes important.1" ... 

Redmore, D., Phosphorus derivatives of nitrogen heterocycles. 3. Carbon-phosphorus bonding in pyridyl-2- and -4-phosphonates, /. Org. Chem., 38, 1306, 1973. 

Carbon-nitrogen bond formation, by reductive amination, 59, 1 Carbon-phosphorus bond formation, 36, 2 Carbonyl compounds, addition of... 

Besides the successful development of asymmetric syntheses with carbon-carbon bond formation, methods for carbon-heteroatom bond formation were also investigated intensively. In this context we developed several practical protocols for carbon-nitrogen, carbon-oxygen, and carbon-phosphorus bond formation. 

The a-methoxylated derivatives are shown to be versatile synthons because of the reactivity of the methoxy group near the nitrogen atom, a-Methoxycarbamates, prepared by anodic oxidation, were used as key intermediates in the synthesis of a-amino acids,200 a new carbon-phosphorus bond-forming reaction,200 and in a new method of acylation of aliphatic amines at the -position.201 The application of this reaction to the synthesis of pyrrolidine, piperidine, and tropane alkaloids is also described.202... 

Additions Forming Carbon-Oxygen, Carbon-Sulfur, Carbon-Nitrogen, and Carbon-Phosphorus Bonds... 

Carbon-Nitrogen and Carbon-Phosphorus Bond Formation (Table 2)... 

Hexacoordinated phosphorus species bearing a formal positive charge have been generated, albeit without a carbon-phosphorus bond. Rather, compounds of the type for which an example is shown as (16) have been prepared with four oxygen and two nitrogen ligands with an overall positive charge. ... 

The fourth edition has been expanded by a chapter on the Formation of Carbon-Phosphorus Bonds and by another on the Formation of Carbon-Deuterium Bonds . The chapter on Alteration of Nitrogen Groups in Carbon-Nitrogen Compounds has been substantially expanded, but the remaining parts of the book have merely been completed by inclusion of preparative processes discovered in recent years. 

General discussion of intra- and intermolecular interactions 3 van der Waals interactions 3 Coulombic interactions 5 Medium effects on conformational equilibria 5 Quantum mechanical interpretations of intramolecular interactions 7 Methods of study 8 Introduction 8 Nmr and esr spectroscopy 8 Microwave spectroscopy (MW) 12 Gas-phase electron diffraction (ED) 12 X-ray crystallographic methods 13 Circular-dichroism spectroscopy and optical rotation 14 Infrared and Raman spectroscopy 18 Supersonic molecular jet technique 20 Ultrasonic relaxation 22 Dipole moments and Kerr constants 22 Molecular mechanic calculations 23 Quantum mechanical calculations 25 Conformations with respect to rotation about sp —sp bonds 27 Carbon-carbon and carbon-silicon bonds 28 Carbon-nitrogen and carbon-phosphorus bonds 42 Carbon-oxygen and carbon-sulphur bonds 48 Conformations with respect to rotation about sp —sp bonds Alkenes and carbonyl derivatives 53 Aromatic and heteroaromatic compounds 60 Amides, thioamides and analogues 75 Conclusions 83 References 84... 

A representation of some nucleophilic displacement reactions utilizing bromoethane (ethyl bromide, CH3CH2Br) as a prototypical primary alkyl substrate upon which the various nucleophiles act. The display of synthetic versatility in the Sn2 reaction producing the many varieties of compounds illustrates carbon-oxygen, carbon-sulfur, carbon-nitrogen, carbon-phosphorus, and carbon-carbon bond formation and should not be taken to exclude other possibilities. The details of the conditions might be specified as in Table 7.4 for each case but are omitted here for brevity. 

The stepwise formation of tropones upon insertion of GO into alkyne dimers coordinated to diiron centers is a commonly found process in iron carbonyl chemistry no triiron complexes are isolated during these processes (e.g., see Refs 14 and 14a). Finally, GO insertion is observed when diiron dimers linked by diacetylene moieties are reacted with diethylamine to give the complexes 6 and 7 (Figure 2) these complexes also contain iron-carbon-nitrogen and iron-carbon-phosphorus bonds. 

NMR is an extremely powerful method for observing the environment of an atom of interest. The element most commonly studied is hydrogen bonded to another element, usually carbon, and is referred to as NMR spectroscopy (sometimes called HNMR, H NMR, P NMR, or proton NMR). The second most commonly studied element is carbon, specifically 13C, bonded to other carbon atoms and to hydrogen atoms. Other elements commonly measured include fluorine, nitrogen, and phosphorus. 

Elimination of trimethylchlorosilane and nitrogen occurs when the (phos-phino)(silyl)diazomethane la is reacted with para-toluenesulfinyl chloride at low temperature. The formation of the four-membered heterocycle 92, obtained in 87% yield, can be rationalized by a multiple-step mechanism involving the formation of the (phosphino)(sulfinyl)carbene 2v. The insertion of the (phosphoryl)(sulfenyl)carbene 91, resulting from a 1,3-oxygen shift from sulfur to phosphorus in 2v, into a carbon-hydrogen bond of a diisopropylamino group readily accounts for the formation of 92.84... 

While breaking of the carbon-to-phosphorus bond is a nuisance in catalysis with organometallic complexes, the breaking of carbon-to-nitrogen and -to-sulfur bonds is a desired reaction in the oil industry. Hydrodenitrification (HDN) and hydrodesulfurisation (HDS) are carried out on a large scale in order to remove nitrogen and sulfur from the fuel feedstocks. 

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