Kinetic acetalization for 1,2- and 1,3-diol protection by the reaction of p-methoxyphenylmethyl methyl ether with DDQ

✍ Scribed by Yuji Oikawa; Takao Nishi; Osamu Yonemitsu

• Publisher: Elsevier Science
• Year: 1983
• Tongue: French
• Weight: 236 KB
• Volume: 24
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)88256-8

✦ Synopsis

When in the presence even in case of tively. 1,2-and 1,3-dials were treated with p-methoxyphenylmethyl methyl ether (MPMME) of DDQ, the kinetically controlled oxidative acetalization occurred smoothly acid-labile compounds to give p-methoxybenzylidene acetals rather stereoselec-DDQ 060, Japan New hydroxy protecting groups with specific properties are still being required in the synthesis of complex natural products, particularly in the area of polyketide derived macrolide and polyether antibiotics. Polyhydroxy functionality present in this class of natural productsl) .

involves a variety of 1,2-and 1,3-diol systems, which are usually protected as cyclic acetals and ketals, primarily because of their ease of both formation and removal, stability under the basic conditions required for alkylation, acylation, etc., and regid conformation.