Substituted perhydrofuropyrans: easy preparation from 2-chloromethyl-3-(2-methoxyethoxy)propene through 3-methylene-1,6-diols

✍ Scribed by Emilio Lorenzo; Francisco Alonso; Miguel Yus

• Book ID: 104209944
• Publisher: Elsevier Science
• Year: 2000
• Tongue: French
• Weight: 184 KB
• Volume: 41
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)00009-5

✦ Synopsis

The reaction of 2-chloromethyl-3-(2-methoxyethoxy)prop-1-ene (1) with an excess of lithium powder and a catalytic amount of naphthalene (2.5%) in the presence of a carbonyl compound (E 1 =R 1 R 2 CO) in THF at -78 to 0°C, followed by treatment with an epoxide [E 2 =R 3 R 4 C(O)CHR 5 ] at 0 to 20°C leads, after hydrolysis, to the expected unsaturated diols 2. When some compounds 2 (2e-h) are successively hydroborated (BH 3 •THF) and oxidised (33% H 2 O 2 and then PCC), the expected perhydrofuropyrans 3e-h are isolated directly.