Conjugate addition of organolithium reagents to diphenylcyclopropenone

✍ Scribed by J. Ciabattoni; P.J. Kocienski; G. Melloni

• Publisher: Elsevier Science
• Year: 1969
• Tongue: French
• Weight: 246 KB
• Volume: 10
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)88038-2

✦ Synopsis

Very little is known concerning the behavior of cyclopropenones toward organometallic reagents. 233 In fact, no reports have appeared regarding the conjugate attack of such reagents on cyclopropenones. 495 We wish to report here the formation of a,B,B-triphenylpropionic acid (7a) and a,B,Y,y-tetraphenylbutyric acid (7b) as a result of the conjugate addition of phenyl--lithium and diphenylmethyllithium, respectively, to diphenylcyclopropenone (L). Normal addition6 of under nitrogen produced aqueous KH2P04 afforded 1. in THF to a solution of phenyllithium7 (slight excess) in THF at O" a red-brown solution. Hydrolysis of the reaction mixture with saturated the known a,B.B-triphenylpropionic acid (7a)8 in approximately 18% -yield9 after recrystallization from cyclohexane, mp 220-221' (lit. a KBr -1 mp 221.5-222O) " m8x (cm 3450-2400 (s, broad), 1700 (s), 1605 (m), 1590 (m), 1500 (s), 1455 (s), and 1420 (m); nmr