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Geminate

Papanikolas J M, Gord J R, Levinger N E, Ray D, Versa V and Lineberger W C 1991 Photodissociation and geminate recombination dynamics of t in mass-seiected, (Cfjj j ciuster ions J. Phys. Chem. 90 8028-40... [Pg.827]

For very fast reactions, the competition between geminate recombmation of a pair of initially fomied reactants and its escape from the connnon solvent cage is an important phenomenon in condensed-phase kinetics that has received considerable attention botli theoretically and experimentally. An extremely well studied example is the... [Pg.860]

Paige M E, Russell D J and Harris C B 1986 Studies of chemical reactivity in the condensed phase. II. Vibrational relaxation of iodine in liquid xenon following geminate recombination J. Chem. Phys. 85 3699-700... [Pg.865]

Batista V S and Coker D F 1996 Nonadiabatic molecular dynamics simulation of photodissociation and geminate recombination of liquid xenon J. Chem. Phys. 105 4033-54... [Pg.865]

CIDNP involves the observation of diamagnetic products fonned from chemical reactions which have radical intemiediates. We first define the geminate radical pair (RP) as the two molecules which are bom in a radical reaction with a well defined phase relation (singlet or triplet) between their spins. Because the spin physics of the radical pair are a fiindamental part of any description of the origins of CIDNP, it is instmctive to begin with a discussion of the radical-pair spin Hamiltonian. The Hamiltonian can be used in conjunction with an appropriate basis set to obtain the energetics and populations of the RP spin states. A suitable Hamiltonian for a radical pair consisting of radicals 1 and 2 is shown in equation (B1.16.1) below [12]. [Pg.1593]

The first application of the time-resolved CIDNP method by Closs and co-workers involved tire Norrish 1 cleavage of benzyl phenyl ketone [24, 25]. Geminate RPs may recombine to regenerate the starting material while escaped RPs may fonn the starting ketone (12), bibenzyl (3), or benzil (4), as shown below. [Pg.1604]

Closs G L and Miller R J 1979 Laser flash photolysis with NMR detection. Microsecond time-resolved CIDNP separation of geminate and random-phase polarization J. Am. Chem. Soc. 101 1639—41... [Pg.1619]

Figure C3.1.7. Time-resolved optical absorjDtion data for the Soret band of photo lysed haemoglobin-CO showing six first-order (or pseudo-first-order) relaxation phases, I-VI, on a logaritlimic time scale extending from nanoseconds to seconds. Relaxations correspond to geminate and diffusive CO rebinding and to intramolecular relaxations of tertiary and quaternary protein stmcture. (From Goldbeck R A, Paquette S J, Bjorling S C and Kliger D S 1996 Biochemistry 35 8628-39.)... Figure C3.1.7. Time-resolved optical absorjDtion data for the Soret band of photo lysed haemoglobin-CO showing six first-order (or pseudo-first-order) relaxation phases, I-VI, on a logaritlimic time scale extending from nanoseconds to seconds. Relaxations correspond to geminate and diffusive CO rebinding and to intramolecular relaxations of tertiary and quaternary protein stmcture. (From Goldbeck R A, Paquette S J, Bjorling S C and Kliger D S 1996 Biochemistry 35 8628-39.)...
Gould I R, Ege D, Mattes S L and Farid S 1987 Return electron transfer with geminate radical ion pairs - observation of the Marcus inverted region J. Am. Chem. Soc. 109 3794-6... [Pg.2995]

Treatment of geminal dihalocyclopropyl compounds with a strong base such as butyl lithium has been for several years the most versatile method for cumulenes. The dihalo compounds are easily obtained by addition of dihalocarbenes to double--bond systems If the dihalocyclopropanes are reacted at low temperatures with alkyllithium, a cyclopropane carbenoid is formed, which in general decomposes above -40 to -50°C to afford the cumulene. Although at present a number of alternative methods are available , the above-mentioned synthesis is the only suitable one for cyclic cumulenes [e.g. 1,2-cyclononadiene and 1,2,3-cyclodecatriene] and substituted non-cyclic cumulenes [e.g. (CH3)2C=C=C=C(CH3)2]. [Pg.117]

An unactivated methyl group can be functionalized by the cyclopalladation of oximes. The equatorial methyl of geminal methyls in steroids or hexapyr-anosides is selectively aceto.xylated by the reaction of the palladation complex 523 of the 3-oxime with lead tetraacetate[467,468]. [Pg.96]

The allylic geminal diacetate 141 undergoes the monoallylation of malonates to give 142 and the two regioisomers 143 and 144[93,94]. The dimethylacetal 145 or ortho esters of aromatic and a,/3-unsaturated carbonyl compounds react with trimethylsilyl cyanide to give the methyl ether of cyanohydrin[95]. [Pg.310]

Just as It IS possible to prepare alkenes by dehydrohalogenation of alkyl halides so may alkynes be prepared by a double dehydrohalogenation of dihaloalkanes The dihalide may be a geminal dihalide, one m which both halogens are on the same carbon or it may be a vicinal dihalide, one m which the halogens are on adjacent carbons... [Pg.372]

Geminal dihalide Sodium amide Alkyne Ammonia... [Pg.372]

Double dehydrohalogenation to form terminal alkynes may also be carried out by heating geminal and vicinal dihalides with potassium tert butoxide m dimethyl sulfoxide... [Pg.373]

Hydrogen halides add to alkynes in accordance with Markovnikov s rule to give alkenyl halides In the presence of 2 moles of hydrogen halide a second addition occurs to give a geminal dihalide... [Pg.385]

Figure 13 20 there are two other vinylic protons Assuming that the coupling constant between the two geminal protons in ArCH=CH2 is 2 Hz and the vicinal coupling constants are 12 Hz (cis) and 16 Hz (trans) describe the splitting pattern for each of these other two vinylic hydrogens... [Pg.543]

Spm-spm splitting of NMR signals results from coupling of the nuclear spins that are separated by two bonds (geminal coupling) or three bonds vicinal coupling)... [Pg.576]

Step 3 Proton transfer from the conjugate acid of the geminal diol to a water molecule... [Pg.718]

The December 2000 issue of the Journal of Chemical Education (pp 1644-1648) contains an article entitled Carbinolamines and Geminal Diols in Aqueous Environmental Organic Chemistry... [Pg.724]

Double dehydrohalogenation (Section 9 7) Reaction in which a geminal dihahde or vicinal dihahde on being treated with a very strong base such as sodium amide is converted to an alkyne by loss of two protons and the two halogen substituents... [Pg.1281]

Geminal dihalide (Section 9 7) A dihahde of the form R2CX2 in which the two halogen substituents are located on the same carbon... [Pg.1284]


See other pages where Geminate is mentioned: [Pg.847]    [Pg.860]    [Pg.861]    [Pg.1594]    [Pg.1596]    [Pg.1596]    [Pg.1596]    [Pg.1604]    [Pg.1607]    [Pg.1609]    [Pg.1611]    [Pg.2421]    [Pg.117]    [Pg.469]    [Pg.372]    [Pg.373]    [Pg.385]    [Pg.542]    [Pg.543]    [Pg.576]    [Pg.580]    [Pg.718]    [Pg.718]    [Pg.718]    [Pg.718]    [Pg.736]    [Pg.743]   
See also in sourсe #XX -- [ Pg.189 ]




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2- Azadienes via geminal disubstitution

Aldehydes conversion to geminal

Aldehydes geminal dialkylation

Alkyl dihalides, geminal

Alkyl geminal substitution

Alkyl halides geminal dihalides

Alkylation geminal

Alkynes from geminal and vicinal dihalides

Allylic geminal dicarboxylates

Anion, geminal diol

Antisymmetrical geminal power

Antisymmetrized Geminal Power

Antisymmetrized geminal products

Antisymmetrized product of strongly orthogonal geminals

Charge separation quantum yield geminate ionization

Coefficients, geminal

Conjugation, geminal effects

Contact approximation geminate recombination

Coulomb interaction geminate recombination

Coupling constants geminal

Cyclopropane, geminally activated

Dehalogenation of geminal dihalocyclopropyl derivatives

Dianions, geminal

Diazoketones conversion to geminal difluoro

Dibromides geminal

Dichlorides geminal

Dihaloalkanes geminal

Diols geminal

Direct Geminal Dialkylation of Ketones

Dithiolates, geminal

Dithiols geminal

Donor-acceptor interaction geminal

Electron transfer geminate radical pairs

Electronic coupling geminate radical pairs

Elimination reactions dehydrohalogenation of geminal and vicinal

Exciton geminate recombination

Explicitly correlated geminals

Exponential model geminate recombination

Extended Geminal Models Roeggen

Gaussian Geminal Methods

Gaussian geminals

Gaussian-type Geminals

Gemin

Gemin

Geminal

Geminal

Geminal (or 1,1-) Addition of an Amide

Geminal -dihalide

Geminal Fluoro, Hetero Alkenes

Geminal acylation

Geminal bond participation

Geminal couphng

Geminal coupling

Geminal coupling constants and

Geminal coupling constants, dependence

Geminal coupling in six-membered rings

Geminal cyclopropane rings

Geminal delocalization

Geminal diacetates

Geminal dialkyl substitution

Geminal dialkylation

Geminal dialkylations

Geminal diamine

Geminal diazides

Geminal dicarboxylates

Geminal dicarboxylic acid

Geminal diesters

Geminal difluoride

Geminal dihalide alkynes

Geminal dihalides

Geminal dihalides alkynes

Geminal dihalides in preparation of alkynes

Geminal dimethyl moiety

Geminal dimethyl substitution

Geminal dinitro compounds

Geminal disubstitution

Geminal effect

Geminal elimination

Geminal excitation operator

Geminal from carbonyl compounds

Geminal functional theory

Geminal functional theory application

Geminal functional theory formal

Geminal group

Geminal halides

Geminal halides reduction

Geminal hydrogens

Geminal interactions

Geminal ligands

Geminal overlap

Geminal position

Geminal power method

Geminal principle

Geminal product wavefunctions

Geminal protons

Geminal regioselectivity

Geminal regioselectivity electron-withdrawing groups

Geminal relationship

Geminal repulsion

Geminal selectivity

Geminal strictly localized

Geminal substituent

Geminal substitution

Geminal vinyl dibromide

Geminal wave functions

Geminal, definition

Geminal, hydrolysis

Geminal-dichromium

Geminally Substituted Nitroalkanes

Geminals

Geminals

Geminate Recombination of Interfacial Charge-Transfer States into Triplet Excitons

Geminate chain termination

Geminate dissociation

Geminate dynamics

Geminate electron-hole

Geminate electron/hole pairs

Geminate escape probability

Geminate excited states

Geminate ion pair

Geminate ion-pair recombination

Geminate ions

Geminate ions recombination

Geminate neutralization

Geminate pair recombination

Geminate pair, lifetime

Geminate pairs

Geminate polarization

Geminate polaron pair

Geminate radical pair

Geminate radical pair primary

Geminate radical pair secondary

Geminate radical recombination. Theory

Geminate recombination

Geminate recombination energetics

Geminate recombination equation

Geminate recombination exciplex dissociation

Geminate recombination in high mobility

Geminate recombination in high mobility systems

Geminate recombination inverted region

Geminate recombination irreversible photoionization

Geminate recombination kinetic rate constants

Geminate recombination kinetics

Geminate recombination normal region

Geminate recombination polar solvents

Geminate recombination proton transfer

Geminate recombination reversible transfer

Geminate recombination spin conversion

Geminate recombination time scale

Geminate recombination transfer reactions

Geminate recombination unified theory

Geminate recombination unimolecular reversible dissociation

Geminate termination

Geminate time dependence

Geminated adsorbed cycloalkanes

Gitonic Geminal Superelectrophiles

HH COSY (geminal, vicinal, -relationships of protons)

Halides geminal dihalides

Halogenation geminal dihalides

Hydroxyl groups geminal

Hyperconjugation geminal

Ionic geminals

Iteration/iterative geminal

Ketones geminal dialkylation

Methyl groups geminal

Onsager radius geminate recombination

Onsagers Theory of Geminate-Ion Recombination

Other analyses of geminate radical recombination

Partially Absorbing Outer Boundary with Geminate Recombination

Photoconduction geminate recombination

Photogeneration geminate recombination

Photoionization geminate recombination

Polaron geminate

Power geminal

Proton, geminate

Recombination, geminal

Reflective Outer Boundary with Geminate Recombination

Silanol geminal

Silanols geminal

Slater geminal methods

Strictly local geminal wave

Strictly local geminal wave function

Strongly orthogonal antisymmetrized geminal

Strongly orthogonal antisymmetrized geminal products

Strongly orthogonal geminal

Taxol. geminal coupling

The Geminal Effect

The LCFC Approach to Geminal Interactions

The effect of a magnetic field on geminate ion-pair recombination

Theory of Lone Pair-Sigma Bond Geminal Interactions

Time-dependent studies of geminate recombination

Tungsten hexafluoride ketones to geminal difluondes

Two-Bond (Geminal) Coupling Constants

Two-bond (geminal) coupling

Vicinal and Geminal Coupling

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