A facile synthesis of diastereoisomeric 1,4-diionic organophosphorus compounds

✍ Scribed by Issa Yavari; Mohammad Reza Islami; Hamid Reza Bijanzadeh

• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 403 KB
• Volume: 55
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(99)00220-3

✦ Synopsis

The addition of dialkyl acetylenedicarboxylates to strong CH-acids in the presence of triphenylphosphine leading to highly functionalized 1,4-diionic organophosphorus compounds is reported, These betaines possess two vicinal stereogenic centers and exist as a mixture of two diastercoisemers. Interconversion between the two diastereoisomeric forms of these 1,4-diiunic compounds via C-H proton exchange reactions of the (Ph)rP÷-CH moieties, preclude their separation. The assignments of the two diastereoisomeric forms of these systems are based on the high-field ~H, ~3C and 31p N-MR data.