50655-53-3Relevant academic research and scientific papers
Synthesis of 1-(2-Aminovinyl)indoles and 1,3′-Biindoles by Reaction of 2,2-Diaryl-Substituted 2 H-Azirines with α-Imino Rh(II) Carbenoids
Khaidarov, Adel R.,Rostovskii, Nikolai V.,Zolotarev, Andrey A.,Khlebnikov, Alexander F.,Novikov, Mikhail S.
, p. 3743 - 3753 (2019/02/14)
An effective and operationally simple method for the preparation of 1-(2-(sulfonamido)vinyl)indoles (SAV-indoles) by the Rh(II)-catalyzed reaction of 2,2-diaryl-2H-azirines with 1-sulfonyl-1,2,3-triazoles has been developed. This method enables the stereo
Rh(II)-carbenoid mediated 2H-azirine ring-expansion as a convenient route to non-fused photo- and thermochromic 2H-1,4-oxazines
Rostovskii, Nikolai V.,Novikov, Mikhail S.,Khlebnikov, Alexander F.,Khlebnikov, Vsevolod A.,Korneev, Sergei M.
supporting information, p. 4292 - 4301 (2013/06/27)
The Rh2(OAc)4-catalyzed domino reaction of 2H-azirines with 2-acyl-2-diazoacetates provides a unique synthetic approach to non-fused 2H-1,4-oxazines. The reaction proceeds via sequential formation of a rhodium carbenoid, an azirinium
Von der basenkatalysierten Ringoeffnung von 2H-Azirinen zu einer α-Alkylierungsmethode von primaeren Aminen
Schulthess, Adrian Heinz,Hansen, Hans-Juergen
, p. 1322 - 1336 (2007/10/02)
It is shown than fluorene-9'-spiro-2-(3-phenyl-2H-azirine) (1) on treatment with various alcohols in the presence of the corresponding alkoxide ions yields N-(9'-fluorenyl)benzimidates 2a-d (Scheme 1). 2,2,3-Triphenyl-2H-aziridine (3) reacts with methanol in a similar manner (Scheme 2).Benzimidates 2a (Scheme 3), 8 (Scheme 4) and 10 (Scheme 5) can easily be deprotonated by butyllithium (BuLi) or lithium diisopropylamide (LDA) in tetrahydrofuran (THF) to 1-methoxy-2-aza-allylanions, that can be alkylated, at C(3), exclusively, by various electrophiles (e.g.R-X (X = I, Br), RCHO or methyl acrylate (see also Scheme 6)).As the acidic hydrolyses (1 N HCl) of benzimidates 9 and 11 leads to the corresponding α-alkylated free amines 15 and 18 (Scheme 7 and 8), benzoyl derivatives 16 and 19 are obtained from the hydrolysis under basic conditions.On the other hand it is observed that a catalyzed Chapman rearrangement of 9 and 11 results in the formation of N-benzoyl-N-methyl derivatives 17 and 20 (Scheme 7 and 8).The described reactions offer a simple method for the α-alkylation of actived primary amines.
165. Low temperature irradiations of 3-phenyl-2H-azirines
Von Sieber, Willi,Gilgen, Paul,Chaloupka, Stanislav,Hansen, Hans-Juergen,Schmid, Hans
, p. 1679 - 1690 (2007/10/05)
2,2,3-Triphenyl-2H-azirine (4a) in a matrix of 2,2-dimethylbutane/pentane 8:3 (DMBP) at -185° gave rise on irradiation with light of 250-350 nm to a new UV.-maximum at 350 nm (Fig. 1). We assign the dipole benzonitrildiphenylmethylide (1a) to this new maximum. Irradiation with monochromatic light of 366 nm destroyed this maximum and the initial absorption curve reappeared (Fig. 2). When the azirine 4a was photolysed in DMBP at -185° in the presence of methyl trifluoracetate (TFEM), the maximum at 350 nm was obtained again. This maximum vanished upon increasing the temperature to -160°. Through gas chromatography we were able to show that 5-methoxy-5-trifluormethyl-2,2,4-triphenyl-3-oxazoline (6 a) was produced. 6 a was also obtained upon irradiation of 4 a at room temperature in the presence of TFEM (scheme 1 and table 1). Modification of the previously described experiment, in which the maximum at 350 nm was extinguished in the matrix due to irradiation at 366 nm gave, after warm up, almost no dipole adduct 6 a (table 1). From these experiments, an extinction coefficient of 17,000 for the 350 nm maximum of 1a, was calculated. These experiments have shown that irradiation of triphenylazirine 4a leads to the dipole 1a, which can be reversed photochemically but not thermally -into azirine 4a. 1a reacts at less than -160° with TFEM to give adduct 6a. The results which were obtained with triphenylazirine 4a could be correspondingly obtained with 2,3-diphenyl-2H- azirine 4b (Fig. 3, scheme 2 and table 2). The dipole 1b showed two UV.maxima at 330 nm (ε = 17,500) and 343 nm (ε = 21,000). Later experiments established, that the two maxima belonged to a single dipole species. The dipole 1c obtained upon irradiation of 2,2-dimethyl-3-phenyl-2H-azirine (4 c) in DMBP at -190°, appears to absorb in the same region as the azirine 4c. The presence of the dipole 1c was univocally established by low temperature trapping experiments with TFEM. The dipole 1a showed no ESR.-spectrum characteristic for a triplet state. We assume therefore, that 1a is in a singlet state. Photolysis of oxazolinone 7 at -190° in DMBP led to the dipole 1a with loss of CO 2. 1a recombines apparently in considerable amount with the CO 2 trapped in the matrix to give starting oxazolinone 7 because the 350 nm-maximum of 1a appeared with low extinction. Irradiation with light of 366 nm into this matrix produced triphenylazirine 4 a. Low temperature trapping experiments with TFEM led to small amounts of 5-methoxy-5-trifluormethyl-2,2, 4triphenyl-3-oxazoline (6a).
