There is still a lot of research devoted to this compound(SMILES：O=C(C1=C(C)C=C(C)N1)OCC)Name: Ethyl 3,5-Dimethyl-2-pyrrolecarboxylate, and with the development of science, more effects of this compound(2199-44-2) can be discovered.
The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Alcoholytic, phenolytic and hydrolytic cleavage of organic compounds by catalysts. II》. Authors are Houben, J.; Fischer, Walter.The article about the compound:Ethyl 3,5-Dimethyl-2-pyrrolecarboxylatecas:2199-44-2,SMILESS:O=C(C1=C(C)C=C(C)N1)OCC).Name: Ethyl 3,5-Dimethyl-2-pyrrolecarboxylate. Through the article, more information about this compound (cas:2199-44-2) is conveyed.
cf. C. A. 25, 3311. As shown recently, trihalomethyl ketones are not only converted stoichiometrically into alkali carboxylates and CHCl3 by aqueous alkali (Reaction 1) but also undergo another, purely catalytic reaction; even in the cold they react with alcs. according to the equation RCOCCl3 + R’OH = RCO2R’ + CHCl3 (Reaction 2). It was thought that an alcoholate was indispensable as the catalyst and that water must be excluded as completely as possible to prevent reaction 1. It was soon found, however, that this conception was erroneous and that the role of catalyst can be played very successfully by certain organic salts, such as alkali acetates, formates, benzoates, etc., and purely inorganic carbonates, bicarbonates, sulfites, nitrites, and reaction 2 can be smoothly effected in systems containing considerable water (10%). Thus, while BzCCl3 is not changed in the least by heating 8 hrs. at 170° in a sealed tube, addition of a droplet of dilute aqueous KOH to its MeOH solution suffices to decompose it at once, with evolution of heat, into BzOMe and CHCl3, Presumably there is first formed a little BzOK which quickly exerts its powerful catalytic effect. Mg(OH)2, shaken a long time in aqueous suspension with BzCCl3, decomposes it almost completely into (BzO)2Mg and CHCl3 but in aqueous MeOH gives 92% BzOMe. Thus, in addition to the possibility of neutralizing aqueous or aqueous alc. alkali by completely neutral compounds such as AcCCl3, BzCCl3, etc., a reaction which may prove useful for preparative and anal. purposes, there is the further possibility of decomposing, also in completely neutral solution, the excess of halogen ketone by subsequent addition of alc. It may thus be possible, by addition of minute amounts of perfectly neutral substances, to produce large quantities of nascent CHCl3, CHBr3, HCN (nitriles also undergo the reaction). The milder conditions (entire absence of strong alkalies) under which reaction 2 can now be effected has made it possible to extend the reaction to other substances which previously had either not reacted at all (phenols) or only with difficulty (menthol), for long and high heating may be employed, if necessary, and the reaction can be carried out in alk., neutral or acid solution; thus, KOAc is effective in AcOH and HCO2K reacts excellently in HCO2H. Hydrolysis of the trihalomethyl ketones can likewise be effected by aqueous solutions of catalytically small quantities of certain salts or, what amounts to the same thing, of alkalies, for these are rapidly converted by the ketone into the catalytic salt. Thus, BzCCl3 is smoothly decomposed into BzOH and CHCl3 by boiling several hrs. with water to which has been added a little KOAc; with water alone there is no hydrolysis even after 7 hrs. at 170°. Reaction 1 is really based on catalytic hydrolysis, the much slower velocity of which, as compared with the catalytic esterification (reaction 2) seems to be due to the slight solubility of the hydrolysis products; its acceleration by a stoichiometric amount of alkali (reaction 1) may in great part be due to the opportunity thus afforded to the BzOH to dissolve; in aqueous Me2CO containing a trace of KOAc, 96% BzOH was obtained from BzCCl3 after refluxing 4 hrs. The ready splitting off of a C atom from the trihalomethyl ketones does not occur with the dihalogen compounds, as far as can be judged from experiments with BzCHCl2, which yields PhCH(OH)CO2H. The following % yields of ester were obtained from the appropriate trichloromethyl ketone and alc. in the presence of a little Na: m-O2NC6H4CO2Me 62, m-H2NC6H4CO2Me 90, Et 2,4-dimethylpyrrole-5-carboxylate 93, Et 2-methylindole-3-carboxylate 85, octyl acetate 70, cetyl benzoate 45. Yield of phenol esters with KOAc as catalyst (reaction temperature in parentheses): PhOBz 80 (120°), p-MeC6H4OBz 90 (230°), o-MeC6H4CO2Bz 80 (230°), menthyl benzoate 58 (150°) (the yield previously obtained with Na was 37%). Below are given, resp., the length of reaction (in days unless otherwise stated) and the % yield of benzoate obtained at 20° from BzCCl3 with various alcs. and 0.5-1 equivalent of different catalysts. MeOH: HCO2K 2, 74; HCO2K + HCO2H 3, 85; KOAc 2, 92; KOAc + AcOH 3, 90; KOBz 1, 81; KNO3 3, 91; Mg(OH)2 1, 92. PrOH: Mg(OH)2 2, 79. iso-BuOH: KOAc 4, 90. Hexyl alc.: KOAc 4, 93. Allyl alc.: KOAc 2, 93. Menthol: KOAc 6 hrs. at 150°, 58. PhOH: 4 hrs. at 120°, 80. o-Cresol: KOAc, 4 hrs. at 130°, 80. p-Cresol: KOAc 4 hrs. at 130°, 90. Although very small amounts of the catalysts are distinctly effective, 0.5-1 equivalent was used to shorten the reaction time as much as possible. The lengths of reaction given were in many cases perhaps unnecessarily long. KHCO3, Na2CO3, Na2SO3 and AcONH4 are also effective, but KNO3, anhydrous or hydrated NH4Cl, K bioxalate, HCl.H2O, H2SO4.H2O and HCl are not effective even after 1 day at 70°. BzCCl3 (2.23 g.) and 0.5 g. KOAc, allowed to stand 1 day in 5 cc. MeOH containing 10% water, gave 81% BzOMe; 2.23 g. of the ketone and 0.5 g. KOAc shaken 25 hrs. in 2.4 cc. MeOH containing 50% water gave 22% ester and 70% unchanged ketone. When BzCHCl2 was allowed to stand with 0.1 equivalent Na in MeOH the alkalinity soon greatly diminished and Cl ions but no CH2Cl2 or BzOMe were formed; with 2 equivalents Na, NaCl was deposited and after standing overnight there was obtained 61% phenylglyoxal di-Me acetal, b13 110-4°.
There is still a lot of research devoted to this compound(SMILES：O=C(C1=C(C)C=C(C)N1)OCC)Name: Ethyl 3,5-Dimethyl-2-pyrrolecarboxylate, and with the development of science, more effects of this compound(2199-44-2) can be discovered.
Reference:
Thiazolidine – Wikipedia,
Thiazolidine – ScienceDirect.com