16881-39-3Relevant articles and documents
A Convenient Preparation of t-Butyl Esters
Widmer, Ulrich
, p. 135 - 136 (1983)
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Ring-Strain Effects in Base-Induced Sommelet–Hauser Rearrangement: Application to Successive Stereocontrolled Transformations
Tayama, Eiji,Watanabe, Kazutoshi,Matano, Yoshihiro
supporting information, p. 3631 - 3641 (2016/07/29)
The base-induced Sommelet–Hauser (S–H) rearrangement of azetidine-2-carboxylic acid ester-derived ammonium salts into 2-aryl-substituted derivatives was demonstrated. The ring-strain of four-membered N-heterocycles enables efficient generation of the desired ylide intermediate and enhances the rate of the S–H rearrangement. The asymmetric version of the rearrangement was characterized by excellent levels of successive chirality transmissions. The regio- and stereo-controlled nucleophilic ring opening of the rearrangement products produced quaternary α-aryl amino acid esters with excellent enantiopurities.
Convenient and Simple Esterification in Continuous-Flow Systems using g-DMAP
Okuno, Yoshinori,Isomura, Shigeki,Sugamata, Anna,Tamahori, Kaoru,Fukuhara, Ami,Kashiwagi, Miyu,Kitagawa, Yuuichi,Kasai, Emiri,Takeda, Kazuyoshi
, p. 3587 - 3589 (2015/11/17)
The utility and applicability of polyethylene-g-polyacrylic acid-immobilized dimethylaminopyridine (g-DMAP) as a catalyst in a continuous-flow system were investigated for decarboxylative esterification. High catalytic activity toward acylation was provided by g-DMAP containing a flexible grafted-polymer structure. During decarboxylation, carboxylic acids and alcohols were converted cleanly using di-tert-butyl dicarbonate (Boc2O) as a coupling reagent, which reduced by-products. In addition, the use of Boc2O resulted in the formation of tert-butyl esters. These esterifications dramatically reduced the reaction time under continuous-flow conditions, with a residence time of approximately 2 min. This highly efficient esterification procedure will provide more practical industrial applications.
Practical one-pot double functionalizations of proline
Huy, Peter,Schmalz, Hans-Guenther
, p. 954 - 960 (2011/05/07)
Solubilization of proline as the triethylammonium salt allows N-protection (as the Boc, Cbz or Moc derivative) and subsequent esterification or amidation of the carboxy terminus to be performed in an efficient one-pot fashion. Based on this concept, highly practical protocols were developed to prepare a series of proline derivatives (including Pro-Ser dipetides, Weinreb amides and N-protected proline esters), which are important intermediates, for instance, for the synthesis of proline-derived peptides, chiral reagents and catalysts for asymmetric synthesis. Georg Thieme Verlag Stuttgart - New York.
