51307-92-7Relevant articles and documents
Collaborative effect of Mn-porphyrin and mesoporous SBA-15 in the enantioselective epoxidation of olefins with oxygen
Berijani, Kayhaneh,Hosseini-Monfared, Hassan
, p. 113 - 120 (2017/11/10)
The rational design of heterogeneous, low cost transition metal complexes that can catalyze olefin with high enantioselectivity and activity has been a challenging goal for the synthetic chemist. In this study a chiral ion pair strategy was used for the synthesis of a biomimetic efficient manganese-tetrapyridylporphyrin (H2TPyP) catalyst for the asymmetric epoxidation of olefins with O2. Complex Mn-TPyP was covalently linked to mesoporous SBA-15 in heme-type environments and its counter ion was replaced by L-tartrate anion (SBA15-[Mn(TPyP)TA]). Chiral and achiral homogeneous analogous of Mn-TPyP were also prepared. The Mn-porphyrin confined in nanoreactors of SBA-15 exhibited enhanced activity (TOF = 652 h?1) and enantiomeric excess (ee 93%) compared with the value obtained when the same chiral catalyst functioned in homogeneous solution (TOF 97 h?1 and ee 83%) in the oxidation of 1-decene with O2/isobutyraldehyde. The high specific surface area, uniformly sized pore channels and site isolated active centers of the catalyst may contribute to the high activity and enantioselectivity. SBA15-[Mn(TPyP)TA] was structurally stable and could be recycled for repeated use. Total turnover number in the oxidation of styrene after five cycles was 47,400 with 86% epoxide selectivity and ee 86%.
Production of tartrates by cyanide-mediated dimerization of glyoxylate: A potential abiotic pathway to the citric acid cycle
Butch, Christopher,Cope, Elizabeth D.,Pollet, Pamela,Gelbaum, Leslie,Krishnamurthy, Ramanarayanan,Liotta, Charles L.
supporting information, p. 13440 - 13445 (2013/09/24)
An abiotic formation of meso- and dl-tartrates in 80% yield via the cyanide-catalyzed dimerization of glyoxylate under alkaline conditions is demonstrated. A detailed mechanism for this conversion is proposed, supported by NMR evidence and 13C-labeled reactions. Simple dehydration of tartrates to oxaloacetate and an ensuing decarboxylation to form pyruvate are known processes that provide a ready feedstock for entry into the citric acid cycle. While glyoxylate and high hydroxide concentration are atypical in the prebiotic literature, there is evidence for natural, abiotic availability of each. It is proposed that this availability, coupled with the remarkable efficiency of tartrate production from glyoxylate, merits consideration of an alternative prebiotic pathway for providing constituents of the citric acid cycle.
Process for synthesis of D1 receptor antagonists
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Page/Page column 8, (2010/01/31)
In one embodiment, the present invention describes the synthesis of a compound of formula and intermediates therefor.
