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Search for "hydrogen donors" in Full Text gives 11 result(s) in Beilstein Journal of Organic Chemistry.
Recent advancements in iodide/phosphine-mediated photoredox radical reactions
Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131
- hydrogenation or hydrogen transfer [40], electrocatalysis coupled with water oxidation [41], and sustained visible-light-induced photocatalysis [42]. Among the different strategies available, the use of a mild photocatalytic process involving hole-driven hydrogen transfer with hydrogen donors or hole scavengers
Halides as versatile anions in asymmetric anion-binding organocatalysis
Beilstein J. Org. Chem. 2021, 17, 2270–2286, doi:10.3762/bjoc.17.145
- the cationic reactive species. Keywords: anion binding; asymmetric catalysis; halide anions; hydrogen donors; noncovalent interactions; Introduction Halogens and the respective anionic halides occupy an essential role in natural and chemical processes [1][2][3][4]. While in chemical syntheses
Photocatalyzed syntheses of phenanthrenes and their aza-analogues. A review
Beilstein J. Org. Chem. 2020, 16, 1476–1488, doi:10.3762/bjoc.16.123
- conditions finally afforded the desired phenanthridine 8.7 in 90% yield [69]. Carbon-based radicals could be likewise generated via a C–H hydrogen-atom transfer path. As an example, ethers were used as hydrogen donors and underwent a C–H cleavage step promoted by a photogenerated tert-butoxyl radical. The so
Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches
Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83
- and HEH act respectively as electron and hydrogen donors. The protocol was efficient for dehalogenations with bromine- and iodine-containing acetophenone derivatives (75–98% yields). However, it was much less efficient with chloro ketones (12–40% yields) and not effective with α-bromo esters and α
Aldehydes as powerful initiators for photochemical transformations
Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76
- resonance flash photolysis (ESRFP) and CIDNP in various solvents, depending on the efficiency of the solvents as hydrogen donors [19]. More specifically, triplet state benzaldehyde (9) dissolved in an efficient hydrogen donor solvent can lead to an α-hydroxybenzyl radical (11) as the only detectable species
Synthesis of novel 13α-estrone derivatives by Sonogashira coupling as potential 17β-HSD1 inhibitors
Beilstein J. Org. Chem. 2017, 13, 1303–1309, doi:10.3762/bjoc.13.126
- semihydrogenation of internal alkynes may be achieved by two main catalytic methods: with molecular hydrogen using Lindlar’s catalyst [25][26] or by transfer hydrogenation with hydrogen donors [27][28]. Additionally, alkynes undergo reduction with diimide to produce cis-alkenes [29]. Li et al. carried out the
Bifunctional phase-transfer catalysis in the asymmetric synthesis of biologically active isoindolinones
Beilstein J. Org. Chem. 2015, 11, 2591–2599, doi:10.3762/bjoc.11.279
- already discussed [21][22][23], the bifunctional nature of organocatalysts plays an important role in this reaction to attain satisfactory levels of enantioselectivity. The presence of additional hydrogen donors such as urea groups positively affected the enantioselectivity both in the presence of chiral
Synthesis of chiral N-phosphinyl α-imino esters and their application in asymmetric synthesis of α-amino esters by reduction
Beilstein J. Org. Chem. 2014, 10, 653–659, doi:10.3762/bjoc.10.57
- the past years [31][32][33][34][35]. They usually served as mild hydrogen donors, but the use of them also made the purification difficult at the same time. Hydrogen gas is a traditional reduction source [36] and silanes and boranes are also well documented as the choices of reduction reagents [37][38
From porphyrin benzylphosphoramidate conjugates to the catalytic hydrogenation of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin
Beilstein J. Org. Chem. 2014, 10, 628–633, doi:10.3762/bjoc.10.54
- levels of hydrogenation on the β-pyrrolic double bonds [12][13]. Most of these methods employ chemicals other than H2 as hydrogen donors to reduce porphyrins into chlorins [14][15][16][17][18]. In our case, we decided to investigate the extent of the direct catalytic hydrogenation with H2 over TPPF20 in
- the template TPPF20 to TPCF20 and TPIF20 is cleaner and also more straightforward than most of the methods employing chemicals other than H2 as hydrogen donors. So far, the results indicate that the reduction is facilitated in polar medium, such as mixtures of ethanol, DMF and triethylamine, and that
Electron and hydrogen self-exchange of free radicals of sterically hindered tertiary aliphatic amines investigated by photo-CIDNP
Beilstein J. Org. Chem. 2013, 9, 437–446, doi:10.3762/bjoc.9.46
- the ground states of our sensitizers can neither function as electron donors nor as hydrogen donors, exchange reactions involving different amine-derived radicals, meaning the intermediacy of different types of radical pairs, are the only remaining explanation for the different exchange rate constants
Hydrogen bonding patterns in the cocrystals of 5-nitrouracil with several donor and acceptor molecules
Beilstein J. Org. Chem. 2005, 1, No. 15, doi:10.1186/1860-5397-1-15
- Figure 9. This is yet another example of a supramolecular assembly hosting acyclic pentamer clusters of water. [31][32][33][34][35][36] The tetrahedral pentameric unit corresponds exactly to that described by Walrafen,[37][38] involving a central H2O molecule where the two hydrogen donors of the central
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