Magnetic Non-equivalence of Methylene Protons and gem-Methyl Groups in Asymmetric Iron Complexes

✍ Scribed by Dr. H. Brunner; E. Schmidt

• Publisher: John Wiley and Sons
• Year: 1969
• Tongue: English
• Weight: 229 KB
• Volume: 8
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.196906161

✦ Synopsis

PCls is added portionwise with vigorous stirring to liquid NH3 at -70 'C. An almost clear solution is obtained which yields a white powder when the NH3 is evaporated off. The weight of the final precipitate reveals that 8 moles of NH3 have been taken up for each mole of PCI5. The product is kept at 15&155 "C and at 5 x 10-3 torr for 30 hours whence 4 moles NH&l/mole PCls sublimes off. The residue is taken up in anhydrous methanol and the resulting solution is filtered off and treated with an equal volume of ether. ( I ) precipitates as fine crystals, which are immediately separated off and dried. About 3 g of ( I ) dissolves in 100 ml CH30H. Yield 46 %. ( I ) decomposes without melting at 200 "C.

Tetrakis(trich1orophospha.zo)phosphonium-chloride (3) and -dichloroiodate

A suspension of ( I ) and PCl5 (molar ratio 1:4) in CHCI3 is prepared and heated under reflux. Liberation of HCI is complete after 3 hours. (3) can be reprecipitated from CzC14 with ccI4. The salt having 1 C l ~ in place of C1-can be obtained as large pale yellow crystals from [P(NH2)4]I and PC15 (molar ratio 15); it is much more readily soluble than (3).