Comparative Study of Regioselective Synthesis of β-Aminoalcohols under Solventless Conditions Catalyzed by Sulfated Zirconia and SZ/MCM-41

Abstract

Sulfated zirconia and SZ/MCM-41 were used as catalysts for the synthesis of β-aminoalcohols via epoxide aminolysis. Sulfated zirconia was prepared by sol-gel and SZ/MCM-41 was obtained by impregnation. Solid catalysts were characterized by XRD, SEM-EDS, UV-Vis, FT-IR pyridine desorption and Nitrogen physisorption. Both acid materials were useful as catalysts, even when they were recycled several times. The β-aminoalcohols were characterized by FT-IR, 1 H-and 13 C-NMR and GC-MS.

Microwave-Enhanced Sulphated Zirconia and SZ/MCM-41 Catalyzed Regioselective Synthesis of β-Amino Alcohols Under Solvent-Free Conditions

“…Our work group has recently shown [ 20 ] that MCM-41-supported sulphated zirconia is an efficient catalyst for the regioselective nucleophilic opening of oxiranes with aniline and benzylamine, under thermal and solvent-free conditions, which motivated us to study the corresponding microwave assisted reaction ( Scheme 1 ).…”

“… a 2a = aniline; 2b = benzylamine; b MW radiation-assisted reaction without catalyst; c MW assisted reaction with SZ; d MW assisted reaction with SZM; e Solvent-free reaction at 60 °C with SZ [ 20 ]; f Solvent-free reaction at 60 °C with SZM [ 20 ]. …”

“…Preparation of the sulphated zirconia supported on MCM-41 (SZM) has been already described. [ 20 ] Siliceous MCM-41 (300 mg) were mixed with zirconium sulphate (15 mL) in methanol (1 wt % S), the heterogeneous mixture was stirred 14 h. Then, the impregnated solid was dried for 6 days at 50 °C and finally calcined at 660 °C for 3 h in air flow.…”

In situ epoxide generation by dimethyldioxirane oxidation and the use of epichlorohydrin in the flow synthesis of a library of β-amino alcohols

“…1 H NMR (400 MHz, acetone- d 6 ) δ 7.44 (d, J = 7.3 Hz, 2H), 7.30 (t, J = 7.5 Hz, 2H), 7.25–7.17 (m, 1H), 7.00 (dd, J = 8.5, 7.4 Hz, 2H), 6.61–6.49 (m, 3H), 5.33 (d, J = 3.0 Hz, 1H), 4.46 (dt, J = 8.0, 4.9 Hz, 1H), 4.06 (t, J = 5.9 Hz, 1H), 3.82 (ddd, J = 10.4, 5.7, 4.5 Hz, 1H), 3.66 (ddd, J = 11.0, 7.8, 6.0 Hz, 1H); 13 C NMR (101 MHz, acetone- d 6 ) δ 149.3, 142.8, 129.6 (2C), 129.2 (2C), 127.8 (3C), 117.5, 114.3 (2C), 67.8, 61.2; IR υ max /cm −1 : 3391 (OH), 2928 (CH), 1601 (N–H), 1502 (arom. ), 1263 (C–O); LRMS (ESI + ) m/z 214 (100%, M + H) [ 30 , 61 ].…”

YCl3-Catalyzed Highly Selective Ring Opening of Epoxides by Amines at Room Temperature and under Solvent-Free Conditions

“…This approach is usually met with some limitations such as kinetically slow reactions that may be due to inefficient activation of epoxides and low regioselectivity. To overcome these issues, many new catalytic methods have been introduced using various catalysts, with aims to enhance the electrophilicity of epoxides through metallic coordination or H-bonding [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. The N-alkylation of amines using cyclic carbonates is also an attractive approach to molecules under discussion [27,28].…”