Synthesis of oxa and dithiazepine azetidinones

✍ Scribed by Douglas O. Spry

• Publisher: Elsevier Science
• Year: 1981
• Tongue: French
• Weight: 172 KB
• Volume: 22
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)81996-1

✦ Synopsis

Oxa and dithiazepine azetidinones are prepared halomethyl sulfide intermediate 5. -from the versatile Lammert and Kukolja have described the reaction of the sulfinyl chloride 1 (R=FT, R'=PNB) with diazomethane to give 2 (R=Ft, R'=PNB) as one major isomer in 27% yield, along with the minor chiral sulfoxide isomer and various amounts of C(2) -C(3) methylene addition products (4O%).'J Using a lower temperature (-20") followed by the addition of excess anhydrous HCl we have isolated 2 (R=Ft, R'=PNB) in 76% overall yield from the penicillin 1 (R=Ft, R'=PNB). The product is a single isomer and is the minor isomer obtained by the previous workers. Other side chains and esters proved equally effective; however, in general, a mixture of sulfoxide isomers resulted tiith no detectable amounts of addition products.