24764-40-7Relevant articles and documents
Frustrated Lewis pair-catalyzed double hydroarylation of alkynes with: N -substituted pyrroles
Guo, Jing,Cheong, Odelia,Bamford, Karlee L.,Zhou, Jiliang,Stephan, Douglas W.
supporting information, p. 1855 - 1858 (2020/02/22)
Metal-free hydroarylation of alkynes with N-substituted pyrroles is shown to be most efficiently mediated by B(C6F5)3 to yield 12 variants of dipyrrole-alkanes, a mono-hydroarylation product and a tetrahydroarylation produ
Metal-free regioselective β-alkylation of pyrroles with carbonyl compounds and hydrosilanes: Use of a Bronsted acid as a catalyst
Nomiyamaa, Shota,Tsuchimotoa, Teruhisa
, p. 3881 - 3891 (2015/03/03)
A Bronsted acid, trifluoromethanesulfonimide [HN(SO2CF3)2], was found to catalyze reductive β-alkylation of pyrroles with carbonyl compounds and hydrosilanes. This metal-free process features lower catalyst loadings compared to the original indium variant and exclusive generation of β-alkylpyrroles.
Organic reactions in ionic liquids: A simple and highly regioselective N-substitution of pyrrole
Le, Zhang-Gao,Chen, Zhen-Chu,Hu, Yi,Zheng, Qin-Guo
, p. 1951 - 1954 (2007/10/03)
In ionic liquids [Bmim][PF6] or [Bmim][BF4], pyrrole replaced the halogen atom of an alkyl halide to give the corresponding N-substituted pyrrole in excellent yield. Benzenesulfonyl chloride, p-methylbenzenesulfonyl chloride and benzoyl chloride reacted similarly with pyrroles to afford the N-substituted pyrroles in quantitative yield. Michael addition reaction of pyrrole with electrophilic olefins was completed in a highly regioselective manner to afford the N-alkylpyrroles.
FORMATION OF 1-SUBSTITUTED PYRROLES IN REACTION OF 2-CHLOROCYCLOPROPANECARBOXALDEHYDES WITH PRIMARY AMINES
Nadim, Al' Mokhana,Romashin, Yu. N.,Kulinkovich, O. G.
, p. 1419 - 1422 (2007/10/02)
Reactions of 2-chlorocyclopropanecarboxaldehydes with primary amines in boiling DMF lead in good yield to 1-substituted pyrroles. 2-Chlorocyclopropanecarboxaldehydes were synthesized by the stereoselective reduction of the corresponding 2,2-dichlorocyclopropanemethanols with lithium tetrahydroaluminate with the subsequent oxidation of the mixture of stereoisomeric 2-chlorocyclopropanemethanols with pyridinium chlorochromate.
- and pyrroles as Thromboxane Synthetase Inhibitors
Martinez, Gregory R.,Walker, Keith A. M.,Hirschfeld, Donald R.,Maloney, Patrick J.,Yang, Diana S.,Rosenkranz, Roberto P.
, p. 890 - 897 (2007/10/02)
Several and pyrroles were prepared and evaluated in vitro as thromboxane synthetase inhibitors in human platelet aggregation studies.A number of structures, e.g. 10b,f,g,i (respective IC50 values: 1 μM, 50 nM, 42 nM, 44 nM) showed superior in vitro inhibition of TXA2 synthetase when compared to the standard dazoxiben (1).However, it was found that in vitro potency did not translate into nor correlate with in vivo activity when these compounds were evaluated in mice in a collagen-epinephrine-induced pulmonary thromboembolism model. (E)-1-Methyl-2--5-(2-carboxyprop-1-enyl)pyrrole (10b) was found to offer protection against collagen-epinephrine-induced mortality in mice, thereby demonstrating that oral administration is an effective route for absorption of this drug.Additional evidence for the oral effectiveness of 10b in lowering serum TXB2 levels was obtained by performing ex vivo radioimmunoassay experiments with rats.A 13-week study of 10b in rats with reduced renal mass was conducted in order to evaluate the role of TXA2 production in hypertension and renal dysfunction.Although serum and urinary TXB2 levels in rats were found to be lowered during this study by 10b, the levels of urinary protein excretion remained comparable to that of the control group.
Gas-phase Heteroaromatic Substitution. Part 4. Electrophilic Attack of t-Butyl Cation on Pyrrole, N-Methylpyrrole, Furan, and Thiophene
Margonelli, Andrea,Speranza, Maurizio
, p. 1491 - 1498 (2007/10/02)
t-Butyl cation, obtained in the gas state from the γ-radiolysis of neopentane has been allowed to react with pyrrole (1), N-methylpyrrole (2), furan (3), and thiophene (4).Experiments have been carried out in the pressure range 50-760 Torr and in the presence of variable concentrations of a gaseous base (NMe3).The reactivity of simple heteroaromatic compounds relative to toluene in competition experiments is found to depend markedly upon the composition of the gaseous reaction environment.The apparent kS/kT ratios decrease slightly with increasing pressure.At atmospheric pressure, these ratios increase with the NMe3 concentration levelling off to a value of 1.0 (1), 2.2 (2), 2.6 (3), and 0.6 (4), at the highest base concentration (PNMe3=10 Torr).Under the same conditions, predominant β substitution occurs in the pyrroles , whereas α-attack is favoured in the case of furan (β:α=9:91) and thiophene (β:α=20:80).The gaseous elecrophile appears rather unselective between the n- and the ?-type centres of furan (O:ring=50:50) and thiophene (S:ring=40:60), while it displays no or very limited substitution on the heteroatom of pyrroles.A mechanism based upon reversible addition of the t-butyl cation to the heteroaromatic nucleus, involving premilinary formation of an electrostatic adduct, is used to account for the formation of the t-butylated products and their isomeric composition.It is concluded that the gas-phase t-butyl alkylation of simple five-membered heteroaromatic compounds is regulated by electrostatic interactions established within the encounter pair.A close correspondence exists between this rationalization of the present gas-phase results and recent theoretical and experimental evidence concerning related alkylation processes.
First Example of Predominant β-Orientation in Electrophilic Substitution of Pyrrole
Speranza, Maurizio
, p. 1177 - 1178 (2007/10/02)
The isomeric distribution of the neutral products from the gas-phase electrophilic attack of 3He3H+, CH3FCH3+, and t-C4H9+ ions on pyrrole provides the first experimental evidence for predominant β-orientation in electrophilic substitution of pyrrole .