Page 1203 - Advanced Organic Chemistry Part A - Structure and Mechanisms, 5th ed (2007) - Carey _ Sundberg

1190 molecular orbitals (cont.) Nazarov reaction, 908–909
of aromatic compounds, 31–32 NB-Enantride©
Index of cyclopropane, 85–86 in enantioselective reduction of ketones, 193
of ethenamine, 46–47 NEER, see nonequilibrium of excited rotamers
of ethene, 39–42, 46–47 neighboring group participation, 419–425
of formaldehyde, 43–46 by acetoxy groups, 419–420
frontier, 29, 44 by alkoxy groups, 421
Hückel, 27–31 by aryl groups, 423–425
of methane, 37–39 by carbon-carbon double bonds, 422–423
pictorial representation of, 35–41 by hydroxy group, 420–421
of polyenes, 27–30
ring size effects on, 421–422
of propenal, 46–47
Newman projection formulas, 128
reactive hybrid orbitals, 784
N-fluoro-N N-dimethylamine, conformation, 84
symmetry adapted, 837–838
N-haloamides
symmetry of, 35–37
radical reactions of, 1040
molecular orbital theory, see MO theory
N-hydroxyphthalimide
molecular structure
in polarity reversal catalysis of radical addition,
computation by DFT methods, 55–56
1034
computation by MO methods, 51
N-hydroxypyridine-2-thione
molecular symmetry
acyl derivatives as radical sources, 979
center of, 132
NICS, see nucleus independent chemical shift
of cycloalkanes, 133
meso compounds, 131–134 nitration, aromatic, 796–800
computational modeling of, 799–800
plane of, 131
relationship to chirality, 131–133 electron transfer mechanism for, 799
More O’Ferrall diagram, see potential energy isomer distribution for substituted benzenes,
diagram, two-dimensional table, 786
Mosher reagent, 209 Lewis acid catalysis of, 797
MO theory, 26–54 mechanism of, 796, 799–800
ab initio methods, 32–35 reagents for, 797
characteristics of, summary, 36 nitrile imines
application of, 41–54 as 1,3-dipoles, 875
in electrophilic aromatic substitution, 780–782 frontier orbitals of, 880–881
computation of enthalpy of formation of nitrile oxides
hydrocarbons, 52, 264–269 as 1,3-dipoles, 875
computation of structure by, 51 frontier orbitals of, 880–881
Hückel, 27–32 nitrile ylides
numerical applications, 50–54 as 1,3-dipoles, 875
perturbational, 41–50 substituent effects on, 882–883
pictorial representation, 35–41 frontier orbitals of, 880–881
PMO theory, see MO theory, perturbational nitro compounds
qualitative application, 41–50 acidity of, 597
semi-empirical methods, 32 in aromatic nucleophilic substitution, 817–820
solvation treatment in, 50–51 reductive denitration by thiolates, 1048
Mulliken electronegativity, 9, 95 in S RN 1 substitution reactions, 1045–1048
correlation with acidity of carboxylic acids, 105
examples of, 1049
Mulliken population analysis, 60–61
nitroethene
as dienophile and ketene synthetic equivalent,
N N-dimethylformamide 862
As solvent, 363, 411–412 nitrogen, molecular
naphthalene electron density by Laplacian function, 94
bond lengths, 18, 751 nitronates, 591
as a Diels-Alder diene, 858–859 S RN 1 substitution reactions, 1045–1048
Friedel-Crafts acylation of, 812–813 nitrones
proton exchange in, 792 as 1,3-dipoles, 875
radical anion of, 990 frontier orbitals of, 880–881
natural bond orbitals, 61–62 nitronium ion
natural population analysis, 61–62 role in electrophilic aromatic substitution, 776