327183-90-4Relevant academic research and scientific papers
Bioproduction of Enantiopure (R)- and (S)-2-Phenylglycinols from Styrenes and Renewable Feedstocks
Sekar, Balaji Sundara,Mao, Jiwei,Lukito, Benedict Ryan,Wang, Zilong,Li, Zhi
, p. 1892 - 1903 (2020/12/22)
Enantiopure (R)- and (S)-2-phenylglycinols are important chiral building blocks for pharmaceutical manufacturing. Several chemical and enzymatic methods for their synthesis were reported, either involving multi-step synthesis or starting from a relatively complex chemical. Here, we developed one-pot simple syntheses of enantiopure (R)- and (S)-2-phenylglycinols from cheap starting materials and renewable feedstocks. Enzyme cascades consisting of epoxidation-hydrolysis-oxidation-transamination were developed to convert styrene 2 a to (R)- and (S)-2-phenylglycinol 1 a, with butanediol dehydrogenase for alcohol oxidation as well as BmTA and NfTA for (R)- and (S)-enantioselective transamination, respectively. The engineered E. coli strains expressing the cascades produced 1015 mg/L (R)-1 a in >99% ee and 315 mg/L (S)-1 a in 91% ee, respectively, from styrene 2 a. The same cascade also converted substituted styrenes 2 b–k and indene 2 l into substituted (R)-phenylglycinols 1 b–k and (1R, 2R)-1-amino-2-indanol 1 l in 95–>99% ee. To transform bio-based L-phenylalanine 6 to (R)-1 a and (S)-1 a, (R)- and (S)-enantioselective enzyme cascades for deamination-decarboxylation-epoxidation-hydrolysis-oxidation-transamination were developed. The engineered E. coli strains produced (R)-1 a and (S)-1 a in high ee at 576 mg/L and 356 mg/L, respectively, from L-phenylalanine 6, as the first synthesis of these compounds from a bio-based chemical. Finally, L-phenylalanine biosynthesis pathway was combined with (R)- or (S)-enantioselective cascade in one strain or coupled strains, to achieve the first synthesis of (R)-1 a and (S)-1 a from a renewable feedstock. The coupled strain approach enhanced the production, affording 274 and 384 mg/L (R)-1 a and 274 and 301 mg/L (S)-1 a, from glucose and glycerol, respectively. The developed methods could be potentially useful to produce these high-value chemicals from cheap starting materials and renewable feedstocks in a green and sustainable manner. (Figure presented.).
Highly Efficient and Robust Enantioselective Liquid–Liquid Extraction of 1,2-Amino Alcohols utilizing VAPOL- and VANOL-based Phosphoric Acid Hosts
Pinxterhuis, Erik B.,Gualtierotti, Jean-Baptiste,Wezenberg, Sander J.,de Vries, Johannes G.,Feringa, Ben L.
, p. 178 - 184 (2017/12/15)
The large-scale production of enantiopure compounds in a cost-effective and environmentally friendly manner remains one of the major challenges of modern-day chemistry. The resolution of racemates through enantioselective liquid–liquid extraction was developed as a suitable solution but has remained largely underused, owing to a lack of highly efficient and robust chiral hosts to mediate the process. This paucity of hosts can in part be attributed to a poor understanding of the underlying principles behind these processes hindering the design of more efficient selectors. A previously untested class of hosts, VAPOL and VANOL derived phosphoric acids, has been studied in depth for the efficient enantioselective liquid–liquid extraction of 1,2-amino alcohols. A systematic investigation of extraction parameters was conducted, revealing many key interactions and DFT calculations illustrate the binding modes for the 1:1 complexes that are involved in chiral recognition. The resulting, now-optimized, procedures are highly robust and easy to implement. They are also easily scalable, as demonstrated by U-tube experiments.
Diastereoselective and Enantiospecific Synthesis of 1,3-Diamines via 2-Azaallyl Anion Benzylic Ring-Opening of Aziridines
Li, Kangnan,Weber, Alexandria E.,Tseng, Luke,Malcolmson, Steven J.
supporting information, p. 4239 - 4242 (2017/08/23)
The 1,3-diamine motif appears in numerous complex molecules, yet there are few methods for the stereoselective construction of this moiety. Herein, we demonstrate a stereocontrolled synthesis of 1,3-diamines, which bear up to three contiguous stereogenic centers, through benzylic ring-opening of aziridines with 2-azaallyl anion nucleophiles. Reactions proceed efficiently (yield up to 95%), diastereoselectively (dr up to >20:1), site selectively, and enantiospecifically to deliver products with differentiated amino groups.
Oxaziridine-mediated enantioselective aminohydroxylation of styrenes catalyzed by copper(II) bis(oxazoline) complexes
Michaelis, David J.,Williamson, Kevin S.,Yoon, Tehshik P.
experimental part, p. 5118 - 5124 (2009/12/01)
We report an oxaziridine-mediated enantioselective aminohydroxylation of olefins catalyzed by a chiral copper(II) bis(oxazoline) complex. A variety of styrenic olefins undergo efficient aminohydroxylation with excellent regioselectivity and synthetically
Catalytic asymmetric hetero diels-alder reactions of N-sulfinyl dienophiles with chiral bis(oxazoline)copper(II) and -zinc(II) triflates
Endeshaw, Molla Mellese,Bayer, Annette,Hansen, Lars K.,Gautun, Odd R.
, p. 5249 - 5259 (2007/10/03)
Asymmetric hetero Diels-Alder (HDA) reactions of N-sulfinyl dienophiles with bis(oxazoline)copper(II) and -zinc(II) triflates are described. The cycloaddition with cyclic and acyclic 1,3-dienes has been studied. The copper catalyst was found to be more ef
