4624-23-1Relevant academic research and scientific papers
Catalytic activation of unstrained C(aryl)–C(aryl) bonds in 2,2′-biphenols
Zhu, Jun,Wang, Jianchun,Dong, Guangbin
, p. 45 - 51 (2018/11/23)
Transition metal catalysis has emerged as an important means for C–C activation that allows mild and selective transformations. However, the current scope of C–C bonds that can be activated is primarily restricted to either highly strained systems or more polarized C–C bonds. In contrast, the catalytic activation of non-polar and unstrained C–C moieties remains an unmet challenge. Here we report a general approach for the catalytic activation of the unstrained C(aryl)–C(aryl) bonds in 2,2′-biphenols. The key is to utilize the phenol moiety as a handle to install phosphinites as a recyclable directing group. Using hydrogen gas as the reductant, monophenols are obtained with a low catalyst loading and high functional group tolerance. This approach is also applied to the synthesis of 2,3,4-trisubstituted phenols. A further mechanistic study suggests that the C–C activation step is mediated by a rhodium(i) monohydride species. Finally, a preliminary study on breaking the inert biphenolic moieties in lignin models is illustrated.
Fungicidal activities of dihydroferulic acid alkyl ester analogues
Beck, John J.,Kim, Jong H.,Campbell, Bruce C.,Chou, Shen-Chieh
, p. 779 - 782 (2008/02/12)
The natural product dihydroferulic acid (DFA, 1) and the synthesized DFA methyl (4a), ethyl (4b), propyl (4c), hexyl (4d), octyl (4e), and decyl (4f) esters were examined for antifungal activity. Test fungi included Saccharomyces cerevisiae (wild type, and deletion mutants slt2Δ and bck1Δ), Aspergillus fumigatus, and A. flavus. Growth inhibition of S. cerevisiae treated with 5 mM DFA or the corresponding esters was 4a, 4b, and 4c >98%; 4d 18.8%; 1 6.4%; 4e 6.2%; and 4f 2.8%, relative to the control. The 50% minimum inhibitory concentrations for the more active propyl, methyl, and ethyl esters were 1.5, 2.1, and 4.0 mM, respectively. Compound 4c inhibited 100% growth of both aspergilli at 6.4 mM.
