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4-Dimethylaminophenyl substituents

A very large acceleration in kisc is observed with p-methoxy and dimethylamino substituents (Table 11.2). This observation is consistent with the solution-phase photochemistry of p-methoxy and p-dimethylaminophenyl azides.The Me, CF3, acetyl, fluoro, and chloro substituents are not sufficiently strong n donors or acceptors to significantly influence the size of feisc (Table 11.2), but the strong n... [Pg.532]

Very large acceleration in /cisc is observed with para-methoxy and dimethylamino substituents (Table 2). This is consistent with the solution-phase photochemistry of para-methoxy and para-dimethylaminophenyl azides. ... [Pg.271]

Borazines with dialkylaminoalkyl [RgN(CH2)n ] substituents on the nitrogen sites have been described in the patent literature. 1,3,5-Tris-(p-dimethylaminophenyl)-2,4,6-trialkylborazines are prepared either by the reaction of p-dimethylaminoaniline with BCI3 followed by Grignard-alkylation 101>, or by reaction of alkyldichloroboranes with p-dimethylaminoaniline 102). The preparation of l,3,5-tris(aminoalkyl)borazines by the reaction 103>, is illustrated by Eq. (24). [Pg.75]

As regards the electrooxidation of the corresponding monomers, they have less anodic Epa values than N-phenylpyrrole even with the nitro substituent and the reactions remain irreversible. The substituents influence the oxidation of these monomers much more than was observed with pentaphenylpyrrole. For example, substitution of a p-methoxy group in the N-phenyl of die latter produces a 20 mV cathodic shift in the Epa value (10). The dimethylaminophenyl and nitrophenyl groups show reversible redox behavior and appear to behave independent of the pyrrole moiety in these derivatives. [Pg.69]

Organon have developed Org 31710 and Org 33628 (Figure 7.2). Org 31710 has the same substituent at position 11 but differs at the 17-position, where it contains a spiro-ether group. In the B-ring, it has a 6P-methyl group. Org 33628 has a acetophenone group instead of a dimethylaminophenyl group and is combined with a methylene-furan substituent at position 17 [12]. [Pg.224]

Bis(4-dimethylaminophenyl)squaraine (Sql) and its derivatives (Sq2-Sq26) all exhibit intense and shape absorption bands in the visible region. Their absorption maxima (A,n, ) vary from 627 nm to 661 nm, depending on the substituent at the nitrogen and in the phenyl ring. The absorption spectral data of these compounds in CH2CI2 are summarized in Table 1. [Pg.520]

With support from labelling, the solvolysis of 2-4-methoxyphenylethyl tosylate in 50 50 CF3CH2OH water is shown to proceed via a symmetrical 4-methoxyphenonium ion (25). °° Azide trapping experiments show a selectivity k lk of 83 mol resulting in an upper limit on the rate constant for solvent trapping of 6 X 10 s . Phenonium ions were obtained as intermediates by the addition of 4-methoxy- and 4-dimethylaminophenyl cations to mono- and tetra-substituted alkenes. These phenonium ions react by several pathways, depending on the aryl substituent, alkene, and solvent. With support from computation, a detailed mechanistic analysis was presented to explain the experimental observations. [Pg.294]

The Sn 1 reaction between various N-Boc 2-oxindoles with 3-alkyl substituents and the carbenium ion formed from bis(4-dimethylaminophenyl)methanol (Michler s hydrol) in the presence of a chiral bis-cinchona alkaloid-Brpnsted acid co-catalyst, gives the a-alkylation product in yields of 58-85% with 70-82% eeP A mechanism is suggested 0 for the reactions. [Pg.354]

Table 11.1 demonstrates that there is a noticeable heavy atom (Br, I) effect on However, the influence of the n donating substituents (OCH3, N(CH3)2) is more pronounced. This is consistent with the solution phase photochemistry of para-methoxy and parfl-dimethylaminophenyl azides, which largely yield azobenzenes on photolysis. It is interesting to note, that both electron donating and withdrawing substituents accelerate ISC. Noticeable acceleration of ISC (by a factor of 5) was also revealed for ortho-aJkyl and ortho,ortho-diaSkyl substituents (Table 11.2). ° Thus, all simple derivatives of phenyinitrene have a kisc value similar or higher than that of parent 52. Table 11.1 demonstrates that there is a noticeable heavy atom (Br, I) effect on However, the influence of the n donating substituents (OCH3, N(CH3)2) is more pronounced. This is consistent with the solution phase photochemistry of para-methoxy and parfl-dimethylaminophenyl azides, which largely yield azobenzenes on photolysis. It is interesting to note, that both electron donating and withdrawing substituents accelerate ISC. Noticeable acceleration of ISC (by a factor of 5) was also revealed for ortho-aJkyl and ortho,ortho-diaSkyl substituents (Table 11.2). ° Thus, all simple derivatives of phenyinitrene have a kisc value similar or higher than that of parent 52.

See other pages where 4-Dimethylaminophenyl substituents is mentioned: [Pg.54]    [Pg.54]    [Pg.206]    [Pg.88]    [Pg.152]    [Pg.304]    [Pg.194]    [Pg.604]    [Pg.235]    [Pg.205]    [Pg.114]    [Pg.578]    [Pg.128]    [Pg.37]    [Pg.165]    [Pg.205]    [Pg.212]    [Pg.205]    [Pg.398]    [Pg.268]    [Pg.720]    [Pg.128]    [Pg.48]    [Pg.2172]    [Pg.5]    [Pg.205]    [Pg.97]    [Pg.498]    [Pg.581]    [Pg.720]    [Pg.16]    [Pg.773]    [Pg.519]    [Pg.389]    [Pg.134]    [Pg.6615]    [Pg.687]    [Pg.207]    [Pg.270]    [Pg.121]   


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4- dimethylaminophenyl

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