4523-52-8Relevant academic research and scientific papers
Palladium-Catalyzed Highly Regioselective Aromatic Substitution of Benzylic Ammonium Salts with Amines
Xu, Ya-Nan,Zhu, Meng-Zeng,Lin, Yu-Kun,Tian, Shi-Kai
supporting information, p. 7169 - 7173 (2019/09/13)
An unprecedented aromatic substitution reaction of benzylic ammonium salts has been developed through palladium-catalyzed C-N bond cleavage. A range of primary and secondary amines participated in a palladium-catalyzed aromatic substitution reaction of benzylic ammonium salts, delivering sterically hindered aromatic amines in moderate to excellent yields with extremely high regioselectivity. Preliminary mechanistic studies permitted successful identification of Π-benzylpalladium complexes and Γ-vinyl allylic amines as key intermediates. This study paves the way for the use of benzylic ammonium salts in the aromatic substitution reactions.
C8-H bond activation vs. C2-H bond activation: From naphthyl amines to lactams
Shi, Renyi,Lu, Lijun,Xie, Hangyu,Yan, Jingwen,Xu, Ting,Zhang, Hua,Qi, Xiaotian,Lan, Yu,Lei, Aiwen
supporting information, p. 13307 - 13310 (2016/11/17)
Pd-catalyzed selective amine-oriented C8-H bond functionalization/N-dealkylative carbonylation of naphthyl amines has been achieved. The amine group from dealkylation is proposed to be the directing group for promoting this process. It represents a straightforward and easy method to access various biologically important benzo[cd]indol-2(1H)-one derivatives.
Resonance-stabilized α-naphthylmethyl carbocations and spiro compounds based thereon: VII. Transformations of α-naphthylmethyl carbocations stabilized by one electron-donor group or peri-fused heteroring
Vinogradova,Filatova,Vistorobskii,Pozharskii,Borovlev,Starikova
, p. 338 - 348 (2007/10/03)
1-Hydroxymethyl- and 1-alkoxymethylnaphthalenes containing dimethylamino and methoxy groups or a heteroring in positions 4 and 5 react with protic and Lewis acids to give 1-naphthylmethyl carbocations. Reactions of the latter with the initial alcohol molecule lead to the formation of oligomerization or dehydrogenation (to aldehyde) products or the corresponding dinaphthylmethanes. In some cases, the process was accompanied by cyclodimerization to form cyclohexadienone spiro derivatives in a small yield. Pleiades Publishing, Inc., 2006.
Internal conversion in 4-substituted 1-naphthylamines. Influence of the electron donor/acceptor substituent character
Suzuki, Kengo,Demeter, Attila,Kuehnle, Wolfgang,Tauer, Erich,Zachariasse, Klaas A.,Tobita, Seiji,Shizuka, Haruo
, p. 981 - 991 (2007/10/03)
The thermally activated internal conversion (IC) taking place in 4- substituted 1-(dimethylamino)naphthalenes (14DMX) and 1-aminonaphthalenes (14ANX) with X = CN, Cl, H, CH3 and OCH3 was investigated in three solvents spanning the polarity scale, hexane, diethyl ether and acetonitrile. In both series 14DMX and 14ANX, the efficiency of the IC reaction decreases substantially when X changes from CN to OCH3, the order in which the electron donor character of the 4-substituent increases. Considerably larger IC reaction rate constants are obtained for the first group of compounds. This difference is connected with the ground state structure of the amino group, which is more strongly twisted for 14DMX (ca. 60°) than for 14ANX (ca. 20°), whereas both sets of 1-naphthylamines are planarised in the S1 excited state. The IC process slows down with increasing solvent polarity for each of the 14DMX and 14ANX molecules. The substituent X and the solvent polarity mainly affect the IC activation energy E(IC). With 14DMX in hexane, E(IC) increases from 10 kJ mol-1 for X = CN to 34 kJ mol-1 for X = OCH3, whereas with, e.g., 14DMCL a solvent polarity dependent increase of E(IC) from 16 kJ mol-1 in hexane to 28 kJ mol-1 in acetonitrile is observed. The height of the barrier E(IC) is governed by the energy gap ΔE(S1,S2) between the two lowest excited singlet states. The influence of δE(S1,S2) on E(IC) is attributed to vibronic coupling caused by the proximity of the S1 and S2 states, which flattens the S1 potential energy surface and thereby lowers the IC barrier when ΔE(S1,S2) becomes smaller. It is assumed that the IC reaction of the 1-naphthylamines passes through a conical intersection, which exists as a consequence of the relative displacement of the S1 and S0 surfaces caused by the different amino twist angles in the two states.
