Carbon nitrogen bond

Pi bonds are more reactive than sigma bonds. Carbon, nitrogen, oxygen and sulfur are the only atoms that commonly form re-bonds. Phosphorous forms tc-bonds with oxygen in nucleotide phosphates such asATR... [Pg.11]

In some molecules, atoms have noble-gas configurations when they share more than one pair of electrons with one or more atoms. Sharing multiple pairs of electrons forms multiple covalent bonds. A double covalent bond and a triple covalent bond are examples of multiple bonds. Carbon, nitrogen, oxygen, and sulfur atoms often form multiple bonds with other nonmetals. How do you know if two atoms will form a multiple bond In general, the number of valence electrons needed to form an octet equals the number of covalent bonds that can form. [Pg.245]

One-bond carbon-nitrogen couplings, Dcn of ca. 3 Hz have been measured by Kelemen et aU for a series of labelled alkoxyamines, the model compounds for nitroxide-trapping studies in free radical copolymerization. Absolute Dcn values have been obtained for some mesoionic compounds and related structures by Jazwinski and Staszewska-Krajewska. " ... [Pg.171]

The situation for carbon-nitrogen couplings is complicated (636). Concerning one-bond carbon-nitrogen couplings it has been suggested that the Fermi contact term is dominant for all CN systems for which isosteric CC systems exist (156). In particular, in most CN systems with formal lone-pairs apart from the Fermi contact term the orbital and spin dipolar terms are operative and non-negligible (636,156). [Pg.436]

The one-bond carbon-nitrogen-15 spin-spin couplings in diazocompounds... [Pg.438]

One-bond carbon-nitrogen coupling 438-439, Two-bond carbon-nitrogen coupling 441,... [Pg.461]

Ester bonds Glyoosylases Ether bonds Peptide bonds Carbon-nitrogen bonds. [Pg.1107]

Carbon-oxygen bonds EC 6.6. Nitrogen-metal bonds Carbon-sulfur bonds Carbon-nitrogen bonds Carbon-carbon bonds Phosphoric ester bonds... [Pg.1107]

ABS copolymer—both sp (from the styrene) and sp C-H bonds carbon-nitrogen triple bond, no carbonyl, OH, or sp C-H. [Pg.1231]

Left and nght bonded carbons linked to the same nitrogen... [Pg.260]

Left bond means " bonded to 4-C right bond, bonded to 5-C " Left and right bonded carbons linked to the same nitrogen. [Pg.267]

Lewis s concept of shared electron parr bonds allows for four electron double bonds and SIX electron triple bonds Carbon dioxide (CO2) has two carbon-oxygen double bonds and the octet rule is satisfied for both carbon and oxygen Similarly the most stable Lewis structure for hydrogen cyanide (HCN) has a carbon-nitrogen triple bond... [Pg.14]

With four bonds carbon already has eight electrons The remaining 12 electrons are added as indicated Both oxygens have eight electrons but nitrogen (less electronegative than oxygen) has only six... [Pg.20]

Azide ion ( N=N=N ) Sodium azide IS a reagent used for carbon-nitrogen bond formation The product IS an alkyl azide... [Pg.328]

Compounds that contain a carbon—nitrogen double bond are capable of stereoisomerism much like that seen in alkenes The structures... [Pg.748]

This IS an unusually high rotational energy barrier for a single bond and indicates that the carbon-nitrogen bond has significant double bond character as the reso nance picture suggests... [Pg.836]

Nucleophiles other than water can also add to the carbon-nitrogen triple bond of nitriles In the following section we will see a synthetic application of such a nude ophilic addition... [Pg.871]

The carbon-nitrogen triple bond of nitriles is much less reactive toward nucleophilic addition than is the carbon-oxygen double bond of aldehydes and ketones Strongly basic nucleophiles such as Gngnard reagents however do react with nitriles in a reaction that IS of synthetic value... [Pg.871]

Arylamines Aniline like alkylamines has a pyramidal arrangement of bonds around nitrogen but its pyramid is somewhat shallower One measure of the extent of this flat tenmg is given by the angle between the carbon-nitrogen bond and the bisector of the H—N—H angle... [Pg.916]

Methods for Carbon-Nitrogen Bond Formation Discussed in Earlier Chapters... [Pg.927]

Nucleophilic acyl substitution (Sections 20 4 20 6 and 20 12) Acylation of am monia and amines by an acyl chloride acid anhydride or ester is an excep tionally effective method for the for mation of carbon-nitrogen bonds... [Pg.928]

In Its overall design this procedure is similar to the Gabriel synthesis a nitrogen nude ophile IS used m a carbon-nitrogen bond forming operation and then converted to an ammo group m a subsequent transformation... [Pg.931]

The preparation of amines by the methods described m this section involves the prior synthesis and isolation of some reducible material that has a carbon-nitrogen bond an azide a nitrile a nitro substituted arene or an amide The following section describes a method that combines the two steps of carbon-nitrogen bond formation and reduction into a single operation Like the reduction of amides it offers the possibility of prepar mg primary secondary or tertiary amines by proper choice of starting materials... [Pg.934]

NMR Similarly carbons that are bonded to nitrogen are more shielded than those bonded to oxygen as revealed by comparing the chemical shifts of methylamme and methanol... [Pg.953]

Rotation about the carbon-nitrogen bond is slow in amides The methyl groups of NJ dimethylformamide are nonequivalent because one is cis to oxygen the other cis to hydrogen... [Pg.1236]

Gabriel synthesis (Section 22 8) Method for the synthesis of primary alkylamines in which a key step is the formation of a carbon-nitrogen bond by alkylation of the potassium salt of phthalimide... [Pg.1284]

In presence of one carbon-nitrogen triple bond —C—C=N In compounds with tendency to dipole formation, e.g., C=C—C=0 In aromatic compounds... [Pg.311]

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