397886-95-2Relevant academic research and scientific papers
2,3-Dihydro-4H-1,3-oxazin-4-ones, novel auxiliaries for the stereoselective synthesis of 1β-methylcarbapenems
Pyun,Jeong,Jung,Kim,Lee,Lee,Kim
, p. 1950 - 1952 (2007/10/03)
Dihydrooxazinones 9, prepared from benzylcyanide in two steps serve as efficient auxiliaries for the stereoselective synthesis of β-methylcarbapenem intermediate 2. Reformatsky-type reactions of 4-acetoxyazetidinone with α-bromopropionyl dihydrooxazinone 10 provided β-methylazetidinones 4 in high diastereoselectivities. The auxiliaries 9 were also easily removed in the Dieckmann cyclization leading to β-methylcarbapenem skeletons. Practical synthesis of β-methylenolphosphates 2 from 4-acetoxyazetidinone 3 was achieved in three steps (61-77% overall yield).
