138-24-9Relevant academic research and scientific papers
Selective monomethylation of primary amines with simple electrophiles
Lebleu, Thomas,Ma, Xiaolu,Maddaluno, Jacques,Legros, Julien
supporting information, p. 1836 - 1838 (2014/02/14)
Direct monomethylation of primary amines with methyl triflate was achieved with high selectivity (up to 96%). The key point of this single methyl transfer stems from the use of HFIP as the solvent that interferes with amines and avoids overmethylation.
Recognition of quaternary ammonium salts with tetrapeptides containing α-aminoisobutyric acid as a conformational constraint
Yanagihara, Ryoji,Katoh, Masaki,Hanyuu, Masayuki,Miyazawa, Toshifumi,Yamada, Takashi
, p. 551 - 556 (2007/10/03)
Tetrapeptides Trp-Aib-Gly-Leu-NH-Ar (Aib:α-aminoisobutyric acid, 2-amino-2-methylpropanoic acid, Ar = phenyl or 3,5-dimethylphenyl) were synthesized. The peptides bound quaternary ammonium salts as guests in CDCl3. For every guest, the binding constant K of the peptide host which has a 3,5-dimethylphenyl group was larger than that of the host which has a phenyl group. ROESY analysis of the complex revealed that the N+-CH3 groups of the guests were close to the aromatic moieties of the host in the complex. The charge in cation guests, the φ-basicity of the host, and the turn conformation of the peptides were important factors for the complexation.
PHOSPHORUS-NITROGEN COMPOUNDS. PART 48. THE REACTIONS OF N,N-DIMETHYLTOLUIDINES WITH PHOSPHORUS(V) CHLORIDES. FORMATION OF A NOVEL HETEROCYCLIC SYSTEM.
Cheng, Ching Yee,Shaw, Robert A.
, p. 185 - 192 (2007/10/02)
The reactions of phosphorus oxychloride, P(O)Cl3, with the three N,N-dimethyltoluidines have been studied.O-toluidine gave after suitable work-up only a "nitrogen-substituted" derivative, P(O)(NMeC6H4Me-2)(OEt)2, whilst the m-analogue gave both "nitrogen-substituted", P(O)(NMeC6H4Me-3)(OEt)2, and "carbon-substituted" products, P(O)(C6H3Me-2-NMe2-4)2(OEt), as well as two purely organic compounds, CH2(C6H3Me-2-NMe2-4)2 and CH(C6H3Me-2-NMe2-4)3.With N,N-dimethyl-p-toluidine in addition to two acyclic 'nitrogen-substituted' products, P(O)(NMeC6H4Me-4)(OEt)2 and P(O)(NMeC6H4Me-4)2(OEt), the chloro- and ethoxy-derivative of a novel eight-membered heterocyclic system, P(O)X (X = Cl or OEt), as well as two organic products, CH2(C6H3Me-5-NHMe-2)2 and CH2(C6H3Me-5-NMe2-2)-(C6H3Me-5-NHMe-2) were isolated.The reaction of thiophosphoryl chloride, P(S)Cl3, with N,N-dimethyl-p-toluidine also gave a similar heterocycle, P(S)Cl.The 1H NMR spectra are discussed and related to the X-ray crystal structures.
CIDNP Effects of Sensitized Photochemical Dediazoniation of Arene Diazonium Salts. Manipulating CIDNP Intensities by the Experimental Conditions
Becker, Heinz G. O.,Pfeifer, Dietmar,Radeglia, Reiner
, p. 1591 - 1597 (2007/10/02)
13C and 15N photo-CIDNP effects were determined for the reversible electron transfer from pyrene to arene diazonium salts on excitation of the charge transfer band at 360 nm.The diazonium salts being the products of back electron transfer ("cage products") show enhanced absorption for 13C(1) and the 15N-enriched diazonium group, whereas the escape products, ArH or 15N2, respectively, yield emission signals.It was shown that the intensities of the CIDNP effects depend on the rates of intersystem crossing kisc within the geminate radical pair, i.e. on the magnetic nucleus used as a probe of the CIDNP effect.Using 1H, 13C or 15N the time domain of observation can be manipulated in the ranges of 90-100 ns, 15-20 ns and 3-5 ns, respectively.Furthermore, the CIDNP intensities depend on the proper balance of the rate of electron back transfer, k-e, and the rate kp of formation of the escape product.Since k-e increases with increasing energy of the geminate radical pair, this balance and therefore the CIDNP intensities vary according to the substituent present and the electron donor used. - Keywords: Photochemistry, Dediazoniation, Electron Transfer, Chemical Induced Nuclear Polarization (CIDNP), Arene Diazonium Salts
Alkylidene Transfer from Monochloroalkylmercury(II) Compounds to Aromatic Amines; Selective C-Alkylation
Barluenga, Jose,Campos, Pedro J.,Roy, Miguel A.,Asensio, Gregorio
, p. 1420 - 1426 (2007/10/02)
αα-Diarylalkane derivatives have been synthesized from monochloroalkylmercury(II) compounds in a noncarbenoid alkylidene transfer reaction which takes place selectively on the aromatic ring.A mechanism is suggested for this process.Intermediate products are prepared by alternative routes to ascertain their participation in the course of the reaction.As a consequence, two different aryl groups can be successively incorporated into the alkane molecule.
