L- p-tolyl

Imidazole, l-(p-tolyl)-pK, 5, 448 <70CHE194) rate constants, 5, 448 70CHE194)... 

Pyrido[2,l-/][l,2,4]triazine-5,6,7,8-tetracarboxylic acid, 4,4a-biphenyl-l-p-tolyl-synthesis, 3, 428 Pyridotropylium cations... 

Improved yields are obtained from p-tolyl-substituted imidazoles and benzimidazoles provided that the 1-nitrogen atom is substituted. l-(p-Tolyl)-2,4,5-triphenylimidazole (130) gives, with benzalaniline, l-(stilben-4-yl)-2,4,5-triphenylimidazole (131), and l-phenyl-2-(p-tolyl)-benzimidazole (132) the stibenyl derivative 133.11... 

Likewise, the l-p-tolyl-2-triisopropylsilylethyl cation 333 is obtained by protonation of l-p-tolyl-2-triisopropylsilylethene 334 (equation 50). Less acidic conditions, i.e. FSO3H without addition of SbFs, are sufficient to generate the carbocation 333 while they are insufficient to generate 331. 

Styrenes with less bulky alkyl groups at silicon, such as 1-phenyl-2-trimethylsilylethene 335, l-p-tolyl-2-trimethylsilylethene 337 and even the relatively more bulky substituted l-p-tolyl-2-dimethylisopropylsilyl ethene 338, on protonation using either FSC>3H/SbF5 or FSO3H, do not lead to solutions of persistent /i-trimethylsilyl-substituted carbocations such as 336 from 335 but undergo fast /i-silyl fragmentation to silyl-free cations such as 78 (equation 51). 

Hi. a-Tolyl- and a-phenyl-fi-silyl-substituted vinyl cations. Protonation of l-(p-tolyl)-2-triisopropylsilylethyne 388a leads to formation of the a-(p-tolyl)-/J-triisopropylsilylvinyl cation 389a (equation 65)114,140. The 13C NMR chemical shifts and /ch coupling constants are summarized in Table 16. 

A comparison of the 13C NMR chemical shift of the para carbon in vinyl cations 389a and 390 and the sp2 hybridized l-(p-tolyl)ethyl cations with an additional 1-cyclopropyl- (391) or 1-methyl substituent (392) (Figure 14)150151 gjVes a qualitative measure of the electron demand of various 1-p-tolyl- substituted sp2- and sp-hybridized carbocations. 

The Cjg—Si bond fragmentation in cation 401 occurs already at temperatures where the corresponding 1-mesityl-, l-(p-tolyl)- and 1 -phenylvinyl-/l-(tri isopropyl Jsi lyl-substi tutcd vinyl cations 375, 389a and 393 are stable. The facile formation of the 1 (p-anisyl)vinyl cation 403 can be ascribed to a second protonation of 401 at the oxygen of the anisyl group. 

In 3,7,10-trimethylsilatranes the -carbons are on the flaps of their ring envelopes and the methyl groups occupy a pseudo-equatorial position in the five-membered rings149,166,167. Therefore, in contrast with the symmetric isomer 40 of 1-phenyl-3,7,10-trimethylsilatrane166, the asymmetric isomer 41 of l-(p-tolyl)-3,7,10-trimethylsilatrane149... 

N1 - ETHANOL. 2-[Pg.104]

The Grignard solution (prepared from 53 g bromtoluene and 7.2 g magnesium in 300 ml of ether) was added dropwise to a solution of 35 g p-dimethylaminopropiophenone in 50 ml ether. The mixture was refluxed for 3 hours. Then the liquid phase was added to 500 parts of ice and 100 parts concentrated hydrochloric acid. l-Phenyl-l-p-tolyl-3-dimethylaminopropanol-l was crystallized. M.P. of hydrochloride of l-phenyl-l-p-tolyl-3-dimethylaminopropanol-1 185°C. 

Methyl-6-oxo-l-p-tolyl-l,6-dihydro-3,5-pyridinedicarbonitrile (79) with carbon disulfide followed by methyl iodide gave 5,7-bismethylthio-2-oxo-l-p-tolyl-l,2-dihydro-l,6-naphthyridine-3-carbonitrile (81), presumably via the intermediate (80) (NaH, PhH, Me2NCHO, CS2[, reflux, 2h MelJ, 20°C then reflux, 30 min 28 %).507... 

When IV reacted with toluene and aluminum chloride, a-l-p-tolyl-/8-1-phenyl-l-desoxy-D-glucitol hydrate (VII), was formed. Similarly, when the acetate of p-/3-D-g ucopyranosyltoluene was employed with benzene as solvent, a-l-phenyI-/3-l-p-tolyl-l-desoxy-D-glucitoI hydrate (VIII), resulted. In the same way a-l-phenyl-/3-l-p-tolyl-l-desoxy-D-... 

Figure 42 Zig-zag ID network propagated by O-H Tr(Cp) hydrogen bonds in the crystal structure of [Ru(r 5-Cp)(r 5-l-p-tolyl-2-hydroxyindenyl)] (Cp = C5H5) [117].

SYNS KETONE, 4-(p-TOLYL)PIPERAZINYL 3,4,5-TRIMETHOXYPHENYL PIPERAZINE. l-(p-TOLYL)-4-... 

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