Synthesis of 2-(buta-1,3-diynyl)-N,N-dimethylanilines Using Reductive Methylation Step

Kulyashova, Alexandra E.; Mikheeva, E. V.; Danilkina, Natalia A.; Балова, Ирина А.

doi:10.1016/j.mencom.2014.03.013

Cited by 4 publications

(8 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the procedure described for the preparation of S2b , 4-amino-3-iodobenzonitrile ( S1g ) (452 mg, 1.85 mmol) was converted into S2g (210 mg, 44%) by the reaction with MeLi (1.16 M in Et 2 O; 1.91 mL, 2.22 mmol) and MeI (150 μL, 2.41 mmol) in THF (6.2 mL) at −78 °C to room temperature for 1 h. Column chromatography: silica gel (hexane/EtOAc = 10/1); 1 H NMR (400 MHz, CDCl 3 ): δ 2.94 (d, J = 5.2 Hz, 3H), 4.76–4.85 (br m, 1H), 6.49 (d, J = 8.6 Hz, 1H), 7.48 (dd, J = 8.6, 1.7 Hz, 1H), 7.88 (d, J = 1.7 Hz, 1H). The 1 H NMR spectrum was in good agreement with that reported …”

Section: Methodssupporting

confidence: 90%

“…The known compounds S1h , S1j , S2a , S2d , S2e , S2f , S2k , S3d , S4 , S5f , S5g , and S6 were synthesized according to the literature. The 1 H NMR spectra of S2c , S2g , and S5b were in good accordance with those reported in the literature. Structures of S1a , S1b , S1c , S1g , S1h , S1i , S1j , S2a – S2j , S3a – S3d , S4 , S5a – S5e , S6 , S7 , S8 are shown in Schemes S1–S5.…”

Section: Methodssupporting

confidence: 89%

“…The 1 H NMR spectrum was in good agreement with that reported. 27 3-Bromo-2-iodo-N-methylaniline (S2h). According to the procedure described for the preparation of S2b, 3-bromo-2-iodoaniline (S1h) (244 mg, 0.818 mmol) was converted into S2h (78.9 mg, 31%) by the reaction with MeLi (1.16 M in Et 2 O; 0.847 mL, 0.982 mmol) and MeI (65.9 μL, 1.06 mmol) in THF (2.7 mL) at −78 °C to room temperature for 10 h. Column chromatography: (gradient 1 to 5% EtOAc in hexane) and amine silica gel (hexane only); colorless oil; IR (neat cm −1 ): 3401 (NH); 1 H NMR (500 MHz, CDCl 3 ): δ 2.88 (d, J = 5.2 Hz, 3H), 4.47−4.58 (br m, 1H), 6.43 (d, J = 8.0 Hz, 1H), 7.00 (dd, J = 8.0, 1.1 Hz, 1H), 7.10 (dd, J = 8.0, 8.0 Hz, 1H); 13 C{ 1 H} NMR (125 MHz, CDCl 3 ): δ 31.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

See 2 more Smart Citations

Gold(I)-Catalyzed Cascade Cyclization of Anilines with Diynes: Controllable Formation of Eight-Membered Ring-Fused Indoles and Propellane-Type Indolines

et al. 2020

View full text Add to dashboard Cite

Heterocycle-fused indoles or indolines are distributed widely in a variety of natural products, bioactive agents, and pharmaceuticals. Herein, we describe the development of gold-catalyzed cascade reactions of anilines with diynes to form eight-membered ring-fused indoles and propellane-type indolines, both of which proceed through an intramolecular 5-endo-dig hydroamination followed by an 8-endo-dig cycloisomerization. Controllable formation of eight-membered ring-fused indoles and propellane-type indolines was achieved through selection of the ligands and/or solvents. Protic solvents such as alcohols or IPr ligand favored the formation of eight-membered ring-fused indoles, whereas the use of Buchwald’s type ligands and/or nonpolar solvents gave propellane-type indoline predominantly. This reaction provides rapid access to two types of fused nitrogen heterocycles from simple aniline derivatives.

show abstract

Section: Methodssupporting

confidence: 90%

Section: Methodssupporting

confidence: 89%

Section: ■ Experimental Sectionmentioning

confidence: 99%

See 1 more Smart Citation

Gold(I)-Catalyzed Cascade Cyclization of Anilines with Diynes: Controllable Formation of Eight-Membered Ring-Fused Indoles and Propellane-Type Indolines

et al. 2020

View full text Add to dashboard Cite

show abstract

“…Catalyst Pd(PPh 3 ) 4 was purchased from Sigma-Aldrich; Co 2 (CO) 8 was purchased from Alfa Aesar. N -Iodomorpholine-hydrogen iodide, methylpropargyl ether 5 , bis(trimethylsilyl)buta-1,3-diyne ( 7 ), ethyl 4-amino-3-iodobenzoate ( 9 ), ethyl 4- N , N -diethyl-3-iodobenzoate ( 10 ) 1-iodo-5-methoxypenta-1,3-diyne ( 25 ), ethyl 2-azidoacetate ( 26 ), ethyl 2-(5-iodo-4-(3-methoxyprop-1-yn-1-yl)-1 H -1,2,3-triazol-1-yl)acetate ( 27 ), and 5-iodo-1-(4-methoxybenzyl)-4-(3-methoxyprop-1-yn-1-yl)-1 H -1,2,3-triazole ( 36 ) were synthesized via known procedures without any modification. Solvents were dried under standard conditions.…”

Section: Experimental Sectionmentioning

confidence: 99%

“…Catalyst Pd(PPh 3 ) 4 was purchased from Sigma-Aldrich; Co 2 (CO) 8 was purchased from Alfa Aesar. N-Iodomorpholine-hydrogen iodide, 65 methylpropargyl ether 5, 108 bis(trimethylsilyl)buta-1,3-diyne (7), 109 ethyl 4-amino-3-iodobenzoate (9), 110 ethyl 4-N,N-diethyl-3-iodobenzoate (10) 111 1-iodo-5-methoxypenta-1,3-diyne (25), 37 36) 37 were synthesized via known procedures without any modification. Solvents were dried under standard conditions.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Intramolecular Nicholas Reactions in the Synthesis of Heteroenediynes Fused to Indole, Triazole, and Isocoumarin

et al. 2020

Self Cite

View full text Add to dashboard Cite

The applicability of an intramolecular Nicholas reaction for the preparation of 10-membered O- and N-enediynes fused to indole, 1,2,3-triazole, and isocoumarin was investigated. The general approach to acyclic enediyne precursors fused to heterocycles includes inter- and intramolecular buta-1,3-diyne cyclizations with the formation of iodoethynylheterocycles, followed by Sonogashira coupling. The nature of both a heterocycle and a nucleophilic group affects the possibility of a 10-membered ring closure by the Nicholas reaction. Among oxacycles, an isocoumarin-fused enediyne was obtained. In the case of O-enediyne annulated with indole, instead of the formation of a 10-membered cycle, BF3-promoted addition of an OH-group to the proximal triple bond at the C3 position afforded dihydrofuryl-substituted indole. For 1,2,3-triazole-fused analogues, using NH-Ts as a nucleophilic functional group allowed obtaining 10-membered azaenediyne, while the substrate with a hydroxyl group gave only traces of the desired 10-membered oxacycle. An improved method for the deprotection of Co-complexes of cyclic enediynes using tetrabutylammonium fluoride in an acetone/water mixture and the investigation of the 10-membered enediynes’ reactivity in the Bergman cyclization are also reported. In the solid state, all synthesized iodoethynylheterocycles were found to be involved in halogen bond (XB) formation with either O or N atoms as XB acceptors.

show abstract

Electrophilic Cyclization of Aryldiacetylenes in the Synthesis of Functionalized Enediynes Fused to a Heterocyclic Core

et al. 2014

View full text Add to dashboard Cite

An efficient strategy for the synthesis of asymmetrically substituted enediynes fused to benzothiophene, benzofuran, and indole was developed. The proposed approach is based on the electrophilic cyclization of diacetylenes and Sonogashira coupling. Thus, iodocyclization of readily available ortho-functionalized (buta-1,3-diynyl)arenes was used as a direct way for the synthesis of 2-ethynyl-3-iodoheteroindenes. These substrates and their modified derivatives were easily converted by Sonogashira coupling with acetylenes to a variety of asymmetrically substituted acyclic enediynes fused to heterocycles. The tolerance of the developed methodology to a variety of functional groups is a great advantage in the synthesis of macrocyclic enediyne systems fused to a heterocyclic core. Synthesis of indole-fused 12-membered macrocyclic dienediyne was achieved using ring-closing metathesis as a key step.

show abstract

Synthesis of 2-(buta-1,3-diynyl)-N,N-dimethylanilines Using Reductive Methylation Step

Cited by 4 publications

References 30 publications

Gold(I)-Catalyzed Cascade Cyclization of Anilines with Diynes: Controllable Formation of Eight-Membered Ring-Fused Indoles and Propellane-Type Indolines

Gold(I)-Catalyzed Cascade Cyclization of Anilines with Diynes: Controllable Formation of Eight-Membered Ring-Fused Indoles and Propellane-Type Indolines

Intramolecular Nicholas Reactions in the Synthesis of Heteroenediynes Fused to Indole, Triazole, and Isocoumarin

Electrophilic Cyclization of Aryldiacetylenes in the Synthesis of Functionalized Enediynes Fused to a Heterocyclic Core

Contact Info

Product

Resources

About