Regioselectivity of glycosylation reactions of galactose acceptors: an experimental and theoretical study

• Enrique A. Del Vigo,
• Carlos A. Stortz and
• Carla Marino

Beilstein J. Org. Chem. 2019, 15, 2982–2989, doi:10.3762/bjoc.15.294

• % CF3COOH, CH2Cl2, 0 ºC, 15 min; g) BnBr, NaH, THF, rt, 16 h; h) BzCl, pyridine, CH2Cl2, rt, 12 h; i) AcOH/H2O, 4:1, v/v, 65 ºC, 6 h. Glycosylation of D-Galp acceptors 1α/β and 2α/β using trichloroacetimidate donors 3 and 4. Glycosylation of acceptors 1α/β using galactofuranosyl iodide 5 as donor. Ratios

Host–guest-driven color change in water: influence of cyclodextrin on the structure of a copper complex of poly((4-hydroxy-3-(pyridin-3-yldiazenyl)phenethyl)methacrylamide-co-dimethylacrylamide)

• Nils Retzmann,
• Gero Maatz and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 2480–2483, doi:10.3762/bjoc.10.259

• with N,N-dimethylacrylamide (6) using 2,2’-azobis(2,4-dimethyl)valeronitril (V-65) as an initiator (Scheme 1). The resulting copolymer 7 is orange colored. The color-changing effects of 7 upon addition of CuSO4 alone and in the presence of γ-CD were investigated and representative images are shown in

Flow Giese reaction using cyanoborohydride as a radical mediator

• Takahide Fukuyama,
• Takuji Kawamoto,
• Mikako Kobayashi and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2013, 9, 1791–1796, doi:10.3762/bjoc.9.208

• % yield (Scheme 4) when the reaction was carried out with 1.6 equiv of ethyl acrylate and 3 equiv of NaBH3CN and 10 min residence time in the presence of V-65 (2,2’-azobis(2,4-dimethylvaleronitrile)) as the radical initiator, which decomposes at a lower temperature than AIBN (Figure 2). For comparison, we

• , channel width: 150 μm), and a fraction collector used for this study. Structures of V-65 and AIBN and their ten hour half-life decomposition temperature. Giese reaction using borohydride-based radical mediators. First screening for the reaction of 1a at different temperatures (90–110 °C) and residence

• times (2–10 min) in the presence of AIBN. Background reduction of 1a with NaBH3CN. Second screening at 70 °C and residence time (5–20 min) in the presence of V-65. Cyanoborohydride mediated Giese reaction of 1b and 1c with ethyl acrylate. Supporting Information Supporting Information File 290: Typical

Radical carbonylations using a continuous microflow system

• Takahide Fukuyama,
• Md. Taifur Rahman,
• Naoya Kamata and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2009, 5, No. 34, doi:10.3762/bjoc.5.34

• carbonylation; radical mediator; V-65; Introduction Placing a reaction mixture fluid inside a microstructured channel network helps gain a high surface area to volume ratio that in turn ensures rapid heat and mass transfer [1][2][3]. Precise control of reaction temperature and residence time, excellent mixing

• ′-azobisisobutyronitrile) as a radical initiator. This was attributed to the rather slow decomposition rate of the AIBN (half-life time: 90 min at 85 °C) in light of the time frame employed for the microflow reaction (residence time, 12 min). When we switched AIBN to a more rapidly decomposing V-65 (2,2′-azobis(2,4

• premature reduction of the key radical. Hence, we anticipated that the combination of low pressure CO/V-65 could be successfully applied to the TTMSS-mediated three component carbonylative-coupling reaction of 1-iodooctane (9) [26][27] in a microflow system using methyl vinyl ketone and acrylonitrile as