Reaction of 1-{(pentamethylcyclopentadienyl)(dicarbonyl)ferrio}-2-(2,4,6-tri-tert-butylphenyl)diphosphene with 1,2,4-triazoline-3,5-diones: formations and structures of the first 1,2-diaza-3,4-diphosphetidines and E,E-1,7-dioxa-4,5,10,11-tetraaza-3,4,8,9-tetraphosphacyclododeca-5,11-diene

Abstract

Reaction of [(q5-C5Me5)(C0)2Fe-P=P-Mes*] 1 (Mes* = 2,4,6-But3C6H2) with Ir2,4-triazoline-3,5-diones [hl=N-C(O)N(R)&O)] 2 (a: R = Ph; b: R = 4-EtOC&) in benzene at ambient temperature affords the first 1,2-diaza-3,4-diphosphetidines as part of the bicyclic compounds 4, whereas in diethyl ether solution the twelve-mem bered macrocycle 5 is obtained.In the series of the four-membered phosphorus-nitrogen ring systems A-F derivatives with the 1,3-diaza-2,4-diphosphetidine-D,l the azatriphosphetidine-E,2 and the cyclotetraphosphane-F skeleton3 were described in the literature. Moreover radicals derived from ring B were detected by EPR e~i d e n c e .~ Here we perform a synthetic approach to the novel 1,2-diaza-3,4-diphosphetidines C.Reaction of [ (q5-C5Mes)( C0)2Fe-P=P-Mes*] 1 5 with the 4-aryl-1,2,4-triazoline-3,5-diones 2 (a: aryl = C6H5; b: aryl = 4-EtOC6H4) in benzene at 20°C lead to the orange-yellow The reaction of 1 and 2 takes a different course, when performed in diethyl ether in the temperature range from -60 to +20"C. Here red crystalline 5a and b are isolated by fractional crystallization. At -40 "C doublets in the 31P NMR spectrum at 6 143 and 345 with the large coupling lJpp 635 Hz are in agreement with the formation of the zwitterionic adduct 3. When warmed up these signals disappear in favour of the doublet resonances of 5a at 6 166.6 and 144.5 (lJpp 220.9 Hz) or 5b at 6 164.6 and 142.7 (lJpp 220.4Hz). With prolonged stirring of the diethyl ether solution of 4, ring opening and a [6 + 61 head-to-tail cyclodimerization of 3 to the macrocycle 5 occurs.The molecular structures of the novel ring systems 4 and 5 could not unambiguously be derived from spectroscopic data? and thus were elucidated by single crystal X-ray diffraction analysis$ of 4a and 5b.The most interesting feature of the structure of 4a is the bicyclic organophosphorus ligand at iron. It consists of a 1,2-diaza-3,4-diphosphetidine which is fused to a 1,2,4-triazolidine-3,5-dione via the atoms N(l) and N(2). The fourmembered ring is puckered [dihedral angle between the planes P(2)-P( 1)-N( 1) and P (2)

Synthesis of Phosphorus-Containing Macrocycles and Cryptands

“…159 The reaction of l,2-bis(bromomethyl)benzene with a N phosphino-substituted S,S-dimethylsulfodiimide leads to the nine-membered ring salt 110 (Scheme 113 (CF^n The (E^E)-l,7-dioxa-4,5,10,ll-tetraaza-3,4,8,9-tetraphosphadodeca-5,11-diene 111 is obtained from the reaction of [(^-CsMes) (CO^Fe-P-P-Mes*] with A1l,2,4-triazoline-3,5-diones in diethyl ether (Scheme 58). [161][162][163][164] The reaction of bis(dithiophosphonic acids) with RCN gives a 1:1 adduct which decomposes to RC(S)-NH2 and cyclic trithiopyrophosphonates 112. The stability of 112 decreases as n increases (Scheme 59). 165 Lithium salts of polyfluorinated alcohols treated with «s-l,3-di-fert-butyl-2,4-dichloro-l,3,2,4-diazadiphosphetidine give rise to the corresponding polyfluoro bis-(alkoxy-bridged) diazadiphosphetidine species 113 (Scheme 60).166…”