Synthesis of methyl 4,6- O-benzylidene-2,3-dideoxy-5-thio-β- dl- threo-hex-2-enopyranoside via hetero-Diels–Alder reaction and unusual stabilities of 1,5-anhydro-4,6- O-benzylidene 2,3-dideoxy-5-thio- dl- threo-hex-2-enitol

• Published in: Tetrahedron Vol. 65; no. 3; pp. 599 - 606
• Main Authors: Watanabe, Yuhya, Sakakibara, Tohru
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 17.01.2009; Elsevier
• Subjects: 5-Thiosugar; C-inside form; Carbohydrates with 4, 5, 6, ... C atoms, dissacharides and oligosaccharides; Carbohydrates. Nucleosides and nucleotides; Chemistry; Chemistry, Organic; Exact sciences and technology; Hetero-Diels–Alder reaction; Optical resolution; Organic chemistry; Physical Sciences; Preparations and properties; Pummerer rearrangement; Science & Technology; 5-Thiosugar; Hetero-Diels–Alder reaction; Pummerer rearrangement; C-inside form; Optical resolution; Hetero-Diels-Alder reaction; Ab initio method; Pummerer reaction; Theoretical study; Oside; Thermodynamic stability; Organic sulfide; Thioaldehyde; Threo stereoisomer; Thioglycoside; Hetero Diels Alder reaction; Chemical synthesis
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2008.11.025

The title compound was prepared via hetero-Diels–Alder reaction of 1-acetoxy-1,3-butadiene and thioaldehyde, followed by Pummerer rearrangement. Different from the corresponding sugar and 5a-carba sugar, C-inside isomer of 1,5-anhydro-4,6- O-benzylidene-2,3-dideoxy-5-thio- dl- thero-hex-2-enitol was found to be thermodynamically more stable than the corresponding O-inside one and these thermodynamic stabilities were corroborated by ab initio calculations. [Display omitted]