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Heteroatom-containing

In the absence of heteroatom containing substituents (e.g. halo-, cyano-), at or conjugated with the radical center, carbon-centered radicals have nucleophilic character. Thus, simple alkyl radicals generally show higher reactivity toward electron-deficient monomers (eg. acrylic monomers) than towards electron-rich monomers (e.g, VAc, S) - Table 3.6. [Pg.113]

The regioselectivity observed in these reactions can be correlated with the resonance structure shown in Fig. 2. The reaction with electron-rich or electron-poor alkynes leads to intermediates which are the expected on the basis of polarity matching. In Fig. 2 is represented the reaction with an ynone leading to a metalacycle intermediate (formal [4C+2S] cycloadduct) which produces the final products after a reductive elimination and subsequent isomerisation. Also, these reactions can proceed under photochemical conditions. Thus, Campos, Rodriguez et al. reported the cycloaddition reactions of iminocarbene complexes and alkynes [57,58], alkenes [57] and heteroatom-containing double bonds to give 2Ff-pyrrole, 1-pyrroline and triazoline derivatives, respectively [59]. [Pg.74]

A hydrogen-bond basicity scale has been developed that can be used to determine the relative basicity of molecules. Table 8.2 gives the p hb values for several common heteroatom containing molecules. This is obtained from the protonated form (conjugated acid) of the base in question. The larger the number, the more basic is that compound. [Pg.332]

Fig. 14 The heteroatom-containing 1,3-diradicals, where the triplet stabilization is depressed by the strengthening of p-Jt -q (denoted by bold lines) and weakening of p-JC-q wavy lines) interaction path... Fig. 14 The heteroatom-containing 1,3-diradicals, where the triplet stabilization is depressed by the strengthening of p-Jt -q (denoted by bold lines) and weakening of p-JC-q wavy lines) interaction path...
Kielbasinski, P. and Mikoiajczyk, M. (2007) Chiral Heteroatom-containing Compounds, in Future Directions in Biocatalysis (ed. T.Matsuda), Elsevier, pp. 159-203. [Pg.116]

An interesting extension of the above reactions in the achiral series is the facile, regioselective, one-pot bicyclization of aminodialkenes leading to a variety of polycyclic heteroatom-containing skeletons (Eq. 4.25) [137]. [Pg.104]

McElroy, N. R., Jurs, P. C. Prediction of aqueous solubility of heteroatom-containing organic compounds from molecular structure. J. Chem. Inf. Comput. Sd. 2001, 41,1237-1247. [Pg.310]

Six-membered heterocycles have also been extensively used to mimic the central pyrazole scaffold of limonabant (382). Merck and Co. has utilised pyiidines (510) [314], and pyrimidines (511) [315] in this capacity. Sanofi-Aventis has also claimed a series of pyridine-based analogues [316], as exemplified by (512) and additionally the non-heteroatom containing terphenyl (513) [317]. [Pg.295]

Rieger et al. described a heteroatom-containing C, symmetric metallocene 13 whose stereoselectivity depended on the activator [28, 29], The resulting PP contained fewer stereoerrors when activated with a combination of TiBA and trityl tetrakis(pentafluorophenyl)borate than with MAO. In addition, the molecular weight was lower with MAO. To explain this, it was proposed that some of the stereoerrors arise by reversible chain transfer to aluminum. [Pg.73]

An enantioselective imino-ene reaction was developed by Lectka to provide ct-amino acid derivatives.27 Aryl alkenes (cr-methyl styrene, tetralene), aliphatic alkenes (methylene cyclohexane), and heteroatom-containing enes, all gave high yields and high ee s of the homoallylic amides (Equation (17)). The mechanism of this reaction has been proposed to proceed through a concerted pathway. This mechanism is evidenced by a large kinetic isotope effect observed in the transfer of H(D). [Pg.564]


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Acid Catalysis with Reactants that Contain Heteroatoms

Bidentate Ligands Containing a Heteroatom-Phosphorus Bond

Carbocations heteroatom-containing

Compounds Containing Heteroatoms

Compounds Containing Three Heteroatoms

Compounds Containing Two Heteroatoms

Compounds Containing a Single Heteroatom

Compounds containing Other Heteroatoms

Compounds that Contain Three Heteroatoms

Compounds that Contain Two Heteroatoms

Containing Heteroatoms

Containing Heteroatoms

Containing One Heteroatom

Containing Two or More Heteroatoms

Cyclic Organotin Compounds Containing Heteroatom Tin Bonds

Diorganotin Alkoxides Containing Tin-Heteroatom Bonds

Diorganotin Salts or Esters Containing Tin-Heteroatom Bonds

Eight-membered Rings containing One Heteroatom

Eight-membered Rings containing Three or More Heteroatoms

Eight-membered Rings containing Two Heteroatoms

Enynes acyclic heteroatom-containing

Five-Membered Heterocycles Containing One Heteroatom

Five-Membered Heterocycles Containing Two Heteroatoms

Five-membered Heterocycles containing One Heteroatom Pyrrole, Furan and Thiophene

Functional Groups Containing Heteroatoms

Heteroatom-Containing Functional Groups

Heteroatom-containing aryl iodides

Heteroatom-containing compounds

Heteroatom-containing pentadienyl

Heteroatom-containing pentadienyl complexes

Heteroatom-containing substituent

Heteroatom-containing systems

Heteroatom-containing systems applications

Heteroatoms, available reagents containing 2. Table

Heterocycles Containing More Than Two Heteroatoms

Heterocycles Containing Unusual Heteroatoms

Heterocycles containing more than One Heteroatom

Hydroboration of Dienes and Heteroatom-Containing Alkenes

Lithiated Carbons Containing Heteroatoms

Lithiated carbons containing heteroatom

Macrocycles Containing Heteroatoms other than Oxygen

Methyl radical heteroatom containing

Multiple-heteroatom-containing sulfur

Organic compounds containing heteroatoms

Organogermanium Alkoxides Containing Germanium-Heteroatom Bonds

Organomagnesium Bromides Containing Heteroatoms

Organometallic compounds containing heteroatoms

Organotin Hydrides Containing Heteroatom-Tin Bonds

Organotin Sulfur Compounds Containing Tin-Heteroatom Bonds

Orientation in azole rings containing three or four heteroatoms

Other Systems containing One Heteroatom

Other Systems containing Three Heteroatoms

Pd-Catalyzed Synthesis of Other Heteroatom-Containing Heterocycles

Photoreactions of Compounds containing Heteroatoms other than Oxygen

Polyenes heteroatom containing

Radicals containing heteroatoms

Reactions with Five-Membered Ring Systems Containing One Heteroatom

Rings Containing Three Heteroatoms The Triazines

Rings containing More than One Heteroatom

Rings containing One Heteroatom

Rings containing Two Heteroatoms

Rings that Contain One Heteroatom

Rings that Contain Three or More Heteroatoms

Rotary Kiln Pyrolysis of Polymers Containing Heteroatoms

Ruthenium and Osmium Complexes Containing Multiple Bonds to Heteroatoms

Seven-membered Rings containing Three or More Heteroatoms

Seven-membered systems containing three or more heteroatoms

Seven-membered systems containing two heteroatoms

Silabenzenoids Containing Heteroatoms

Systems containing Four Heteroatoms

Systems containing Heteroatoms Other than Nitrogen

Systems containing Nitrogen and Other Heteroatoms

Systems containing Nitrogen as the only Heteroatom

Systems containing Other Heteroatoms

Systems containing Oxygen as the only Heteroatom

Systems containing Sulphur as the only Heteroatom

Systems containing Three Heteroatoms

Systems containing Three Identical Heteroatoms

Systems containing Two Different Heteroatoms

Systems containing Two Identical Heteroatoms

Tellurium-containing heterocycles with two heteroatoms

Use of Heteroatom-Containing Dienes

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