61734-40-5Relevant articles and documents
Hydrolyses of 2-Trimethylsilyl N1-Heterocycles. Involvement of Zwitterions in the Hydrolysis of 2-(Trimethylsilyl)-N-methylimidazole, 2-(Trimethylsilyl)pyridine, and 2-((Trimethylsilyl)methyl)-N-methylimidazole
Brown, R. S.,Slebocka-Tilk, H.,Buschek, J. M.,Ulan, J. G.
, p. 5979 - 5984 (1984)
The title N-containing aromatic heterocycles (1,2, and 4, respectively) with a trimethylsilyl substituent at the 2-position hydrolize relatively rapidly to form trimethylsilanol and the corresponding 2-H heterocycle.In the case of 2-((trimethylsilyl)methyl)-N-methylimidazole (4) the heterocyclic product is N,2-dimethyl imidazole. pH vs. log kobsd profiles establish that the reaction proceeds faster at high than low pH and that above the pKa of the heterocyclic base the reaction is independent of pH. 2-(Trimethylsilyl)-N-methylpyridinium iodide (6) and 2-(trimethylsilyl)- N,N'-dimethylimidazolium iodide (5) salts hydrolyze with a first-order dependence on -> above pH 6 with no evidence for a pH-independent region at high pH.F- accelerates the reactions of 1 and 2 markedly at low pH but has no effect at pH 12.5.The results indicate that the dominant mechanism for hydrolysis of the title compounds over most of the pH/rate profile involves nucleophilic attack of OH- on the trimethylsilyl unit of the N-protonated base, the leaving group being the zwitterion (ylide) of the heterocycle.The bimolecular constants for attack of OH- on protonated 1 and 2 are comparable to those observed for attack of OH- on 5 and 6, respectively.Compound 1 a below pH 5 attacked by H2O as is 4, but such is not observed for 2.Only compound 4 suffers nucleophilic attack of OH- on the deprotonated base.For 1 and 2 at low pH, F- successfully competes with the intrinsically more nucleophilic OH- because the latter's concentration is so low, but at high pH the reaction proceeds entirely via OH- attack.
METHOD FOR ALKYLATING A MOLECULE OR AN ION
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Page/Page column 34, (2019/04/16)
The present invention relates to a method for alkylating a molecule or an ion, wherein the molecule or the ion is alkylated by reacting it with an alkylating agent, wherein the alkylating agent is a compound according to formula (1) or a compound according to formula (4). In the formulae (1) and (4), R1 is a substituted C1-20-alkyl group, an unsubstituted C1-20-alkyl group, a substituted C3-20-cycloalkyl group or an unsubstituted C3-20-cycloaalkyl group, R2 is a substituted or unsubstituted C1-20 hydrocarbon residue or a hydrogen atom, R3 is a substituted or unsubstituted C1-20 hydrocarbon residue or a hydrogen atom, R4 and R5 are linked with each other to form an aromatic group or are independently from each other selected from the group consisting of a hydrogen atom, substituted and unsubstituted C1-20 hydrocarbon residues and electron withdrawing groups, R10 to R13 are independently from each other selected from the group consisting of a hydrogen atom, a substituted C1-20-alkyl group, an unsubstituted C1-20-alkyl group, a substituted C3-20-cycloalkyl group and an unsubstituted C3-20-cycloaalkyl group and A- is an anion.
TWISTED PI-ELECTRON SYSTEM CHROMOPHORE COMPOUNDS WITH VERY LARGE MOLECULAR HYPERPOLARIZABILITIES AND RELATED COMPOSITIONS AND DEVICES
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, (2010/12/26)
Unconventional twisted π-electron system electro-optic (EO) chromophores/compounds, compositions and related device structures. Crystallographic analysis of several non-limiting chromophores reveals, for instance, large ring-ring dihedral twist angles and
4-phenyl-tetrahydro-furano-pyridines and anti-depressant pharmaceutical compositions containing same
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, (2008/06/13)
The invention relates to 4-phenyl-tetrahydro-furano-pyridines of the formulas STR1 wherein R1 to R5 are variously defined. The compounds of the invention are intended to be used as anti-depressants with, in particular, thymoleptic an
Solvolysis of Di-2-pyridylketone Methiodide
Williams, R.L.,Neergaard, Sandra
, p. 1549 - 1550 (2007/10/02)
Di-2-pyridylketone methiodide undergoes a facile nucleophilic substitution reaction with various alcohols followed by subsequent cleavage and elmination of pyridinium methiodide and the correspoing picolinates.
