Enzymes are biological catalysts that produce large increases in reaction rates and tend to be specific for certain reactants and products. 25383-99-7, Name is Sodium 2-((2-(stearoyloxy)propanoyl)oxy)propanoate, molecular formula is C24H43NaO6, belongs to Benzisoxazole compound. In a document, author is Wang, Kaifeng, introduce the new discover, Category: Benzisoxazole.
Theoretical Insights into Ester-Directed Reactions between Propiolates with 1,2-Benzisoxazoles by Au(I) Catalyst: [4+2]-Annulation versus Michael-Type Products
Au(I)-catalyzed selective reactions of Et- and Bu-t-substituted propiolates (1a and 1a’) with 1,2-benzisoxazole(2a) provide a new strategy for purposefully access to desired bioactive heterocycles. Using DFT calculations, we have systematically investigated the detailed mechanisms and origins of the ester-controlled chemoselectivity. The calculated results indicated that both reactions are initiated by LAu+ pi-coordination, N nucleophilic attack, and NTf2–assisted stepwise H-shift, generating a nitrilium species identified as a common and requisite intermediate, which is significantly different from the experimentally proposed 6-alkoxy-1,3-oxazin-1-ium intermediate. Starting from the nitrilium intermediate, the newly established nucleophilic cyclization, alkene release, and NTf2–assisted stepwise protodeauration provides [4 + 2]-annulation product P-1, while the nitrilum dissociation, O nucleophilic attack, and NTf2–assisted stepwise protodeauration generates Michael-type product P-2. Further explorations showed that Bu-t-controlled chemoselectivity of P-1 over P-2 can be attributed to the energy favorable aromaticity of selective-determining nucleophilic cyclization TS. With substitution of Bu-t by Et group, the reversal of chemoselectivity to P-2 formation might be closely related to the presence of extremely unstable Et cation in ethylene release TS leading to P-1.
Balanced chemical reaction does not necessarily reveal either the individual elementary reactions by which a reaction occurs or its rate law. In my other articles, you can also check out more blogs about 25383-99-7. Category: Benzisoxazole.
Reference:
Benzisoxazole – Wikipedia,
,Benzisoxazole – an overview | ScienceDirect Topics