126923-25-9Relevant academic research and scientific papers
Asymmetric azidohydroxylation of styrene derivatives mediated by a biomimetic styrene monooxygenase enzymatic cascade
Franssen, Maurice C. R.,Hollmann, Frank,Martínez-Montero, Lía,Paul, Caroline E.,Süss, Philipp,Schallmey, Anett,Tischler, Dirk
, p. 5077 - 5085 (2021/08/16)
Enantioenriched azido alcohols are precursors for valuable chiral aziridines and 1,2-amino alcohols, however their chiral substituted analogues are difficult to access. We established a cascade for the asymmetric azidohydroxylation of styrene derivatives leading to chiral substituted 1,2-azido alcohols via enzymatic asymmetric epoxidation, followed by regioselective azidolysis, affording the azido alcohols with up to two contiguous stereogenic centers. A newly isolated two-component flavoprotein styrene monooxygenase StyA proved to be highly selective for epoxidation with a nicotinamide coenzyme biomimetic as a practical reductant. Coupled with azide as a nucleophile for regioselective ring opening, this chemo-enzymatic cascade produced highly enantioenriched aromatic α-azido alcohols with up to >99% conversion. A bi-enzymatic counterpart with halohydrin dehalogenase-catalyzed azidolysis afforded the alternative β-azido alcohol isomers with up to 94% diastereomeric excess. We anticipate our biocatalytic cascade to be a starting point for more practical production of these chiral compounds with two-component flavoprotein monooxygenases.
A hafnium-based metal-organic framework as an efficient and multifunctional catalyst for facile CO2 fixation and regioselective and enantioretentive epoxide activation
Beyzavi, M. Hassan,Klet, Rachel C.,Tussupbayev, Samat,Borycz, Joshua,Vermeulen, Nicolaas A.,Cramer, Christopher J.,Stoddart, J. Fraser,Hupp, Joseph T.,Farha, Omar K.
supporting information, p. 15861 - 15864 (2015/02/19)
Porous heterogeneous catalysts play a pivotal role in the chemical industry. Herein a new Hf-based metal-organic framework (Hf-NU-1000) incorporating Hf6 clusters is reported. It demonstrates high catalytic efficiency for the activation of epoxides, facilitating the quantitative chemical fixation of CO2 into five-membered cyclic carbonates under ambient conditions, rendering this material an excellent catalyst. As a multifunctional catalyst, Hf-NU-1000 is also efficient for other epoxide activations, leading to the regioselective and enantioretentive formation of 1,2-bifuctionalized systems via solvolytic nucleophilic ring opening.
Regioselective intramolecular dipolar cycloaddition of azides and unsymmetrical alkynes
Brawn, Ryan A.,Welzel, Morgan,Lowe, Jason T.,Panek, James S.
supporting information; experimental part, p. 336 - 339 (2010/03/25)
(Figure presented) Enantioenriched allenylsilanes are used in three-component propargylatlon reactions with aldehydes and silyl ethers to form syn-homopropargylic ethers that contain an imbedded azide. These materials then undergo thermally Induced intram
Intramolecular azide-alkyne [3 + 2] cycloaddition: Versatile route to new heterocyclic structural scaffolds
Li, Rongti,Jansen, Daniel J.,Datta, Apurba
experimental part, p. 1921 - 1930 (2009/06/28)
Investigating the relatively unexplored intramolecular version of the azide-alkyne [3 + 2] cycloaddition, the present studies demonstrate the utility of the above reaction in the synthesis of a variety of as yet unreported heterocyclic structural scaffolds. The approach involved initial installation of strategic azide and alkyne moieties on a common structural framework, followed by their intramolecular cycloaddition studies. The pivotal azidoalkyne intermediates were efficiently accessed from a variety of easily available starting materials such as olefins, epoxides, amino acids, amino alcohols, ketones etc. The key reactions for incorporation of the azide functionality into the desired framework involved azidolysis of epoxides, displacement of hydroxy groups with azide nucleophiles, and diazo transfer on amine. Attachment of the desired alkyne functionalities was accomplished by either N-, or, O-alkylation with appropriate propargylic halides. The azidoalkynes thus prepared underwent smooth intramolecular cycloaddition, resulting in a variety of novel triazolooxazine and triazolopyrazine derivatives. Interestingly, unlike in the intermolecular version, metal catalysis was not necessary for the performance of the above cycloadditions. It is expected that the results from the present studies and its further extension will provide a potentially fertile pathway to a variety of unique chemical entities of structural and biological significance.
The regioselective and stereospecific substitution of unsymmetrical 1,2-diols using the 1,3,2λ5-dioxaphospholane methodology
Pautard-Cooper, Anne,Evans Jr., Slayton A.,Kenan Jr., William Rand
, p. 1603 - 1610 (2007/12/18)
Stereo specific tosylate (-OTs) or azide (N3-) substitution at the C-4 stereocenter of a monosubstituted 1,3,2λ5-dioxaphospholane (the equivalent of the C-2 stereocenter in an unsymmetrical 1,2-diol) is readily achieved by treatment with either P-toluenesulfonic acid (P-TsOH) in tetrahydrofuran solvent or P-TsOH/sodium azide in acetonitrile solvent, respectively.
Synthesis of Homochiral Amino Alcohols, Aziridines and Diamines via Homochiral Cyclic Sulphites
Lohray, Braj B.,Ahuja, Jaimala R.
, p. 95 - 97 (2007/10/02)
Vicinal diols react with thionyl chloride to give 1,2-cyclic sulphites in quantitative yield, which undergo facile ring opening by lithium azide in dimethylformamide to yield azido alcohols and the latter in turn have been stereoselectively transformed into amino alcohols, aziridines and diamines.
