Synthesis of 2,6-Bis(2-oxazolinyl)phenylplatinum(II) NCN Pincer Complexes by Direct Cyclometalation. Catalysts for Carbon-Carbon Bond Formation

摘要: 1,3-Bis(4‘,4‘-dimethyl-2‘-oxazolinyl)benzene (5a) and 5-nitro-1,3-bis(4‘,4‘-dimethyl-2‘-oxazolinyl)benzene (5b) were heated in dry acetic acid with K2PtCl4 to give the corresponding 2,6-bis(4‘,4‘-dimethyl-2‘-oxazolinyl)phenylplatinum(II) chloride complexes 6a 6b 49 11% yield, respectively. The X-ray structure of is reported. main side product observed platination 5a was identified as di(2-methyl-2-N-acetyl)propyl isophthalate. In contrast, use Pd(OAc)2 this protocol, followed by addition LiBr, gave 2,6-bis(4‘,4‘-dimethyl-2‘-oxazolinyl)phenylpalladium(II) bromide only 3% yield. Treatment AgOTf AgSbF6 acetone quantitatively cationic 2,6-bis(4‘,4‘-dimethyl-2‘-oxazolinyl)phenyl(aquo)platinum(II) 15a 15b. Similarly treatment 4-nitro-2,6-bis(4‘,4‘-dimethyl-2‘-oxazolinyl)phenyl(aquo)platinum(II) trifluoromethanesulfonate (15c) (72%). Complexes 15a−c, together 2,6-bis(4‘,4‘-...