The simple and selective synthesis of 3-amino-2,2-difluorocarboxylic esters and difluoro-β-lactams using ethyl bromodifluoroacetate in the presence of rhodium catalyst

Synthesis and chemistry of α-iodoperfluoroacid esters

“…Reaction times and isolated yields are reported in Table 1. Yields from methyl perfluoropropionate (3), perfluorooctanoate (4), and hexafluoroglutarate (5) were similar to that from 1. Despite its bifunctionality, methyl hexafluoroglutarate (5) gave only the monoiodo derivative.…”

“…A variation on this reaction entails prior conversion to O-silylketene acetals [2], from which chiral b-hydroxy esters have been obtained [3]. Ethyl halodifluoroacetates are widely used as building blocks for complex structures incorporating the -CF 2 COmoiety [4]. Halodifluoroacetate esters are also good difluorocarbene precursors for cyclopropanation [5] and trifluoromethylation [6] reactions.…”

Ethyl dibromofluoroacetate: a versatile reagent for the synthesis of fluorinated molecules

“…42 Based on their previous work regarding the Rhcatalyzed synthesis of difluoro-b-lactams from imines using Et 2 Zn, 43 the group of Ando looked at the same reaction using EDBFA in place of ethyl bromodifluoroacetate. 41 Manganese is lesstoxic and cheaper than chromium salts but is coated by an outer shell of oxide, which requires a preliminary activation (Mn*).…”

Stereoselektive und katalytische Reformatsky‐Reaktionen

“…Ebenso empfiehlt sich die rhodiumvermittelte Reformatsky‐Reaktion zur Synthese von Difluorcarbonsäureestern und Difluor‐β‐lactamen 20. Interessanterweise wurde hierbei die selektive Synthese von β‐Lactamen oder β‐Aminoestern durch Wasserspuren beeinflusst 20b…”