61695-12-3Relevant articles and documents
Toward a Porphyrin-Style NHC: A 16-Atom Ringed Dianionic Tetra-NHC Macrocycle and Its Fe(II) and Fe(III) Complexes
Anneser, Markus R.,Elpitiya, Gaya R.,Powers, Xian B.,Jenkins, David M.
, p. 981 - 987 (2019/02/26)
N-heterocyclic carbenes (NHCs), and macrocyclic NHCs in particular, have been applied successfully to the stabilization of high oxidation states on transition metal complexes. This access to high oxidation states has enabled their application in oxidative catalysis including aziridination and epoxidation. However, the number of macrocyclic tetra-NHC ligands is still limited, especially those featuring anionic charge, which is beneficial in this regard. In this manuscript, we report a facile and high yielding synthesis for only the second example of such a dianionic, macrocyclic tetra-NHC ligand. This 16-atom macrocycle has the ring size and charge of a porphyrin but with the increased electron donation of NHCs. Its Fe(II) and Fe(III) complexes are reported, and their reactivities for ligand addition and oxidation were tested. Multiple oxidation catalysis reactions were tested with both the Fe(II) and Fe(III) complexes with reagents such as trimethylamine-N-oxide, oxygen (from air), diazodiphenylmethane, and P-tert-butyl-dibenzo-73phosphanorbornadiene (tBuPA) to explore the possibilities for single site oxidation reactions.
Ditelluride-promoted diphosphene transfer from a cyclotriphosphane to 2,3-dimethylbutadiene: characterization of di(aryltelluro)diphosphanes
Meyer, H. U.,Severengiz, T.,Mont, W. W. du
, p. 691 - 694 (2007/10/02)
The cleavage of tri-tert-butylcyclotriphosphane 1 with di(4-methylphenyl)ditelluride 2 leads to 1,2-di-tert-butyl-1.2-di(4-methylphenyltelluro)diphosphane 3 and tetra-tert-butylcyclotetraphosphane.When 1 is heated with 2 in the presence of 2,3-dimethylbutadiene, the diphosphene trapping product 1,2-di-tert-butyl-4,5-dimethyl-1,2-diphosphacyclohex-4-ene 5 can be detected.The salt elimination reaction of tert-butyldichlorophosphane with 4-methylphenyltellurotelluromagnesium bromide leads mainly to 3 and ditelluride 2.Tellurophosphane 6 and 1,2-di-tert-butyl-1,2-di(aryltelluro)diphosphanes 3. 7 (7 : aryl = 2,4,6-triisopropylphenyl) are available in fair yields from di-tert-butylchlorophosphane or 1,2-di-tert-butyl-1,2-dichlorodiphosphane with metal tellurolates.At 90 deg C with 2,3-dimethylbutadiene, 7 acts as a source of 1,2-di-tert-butyldiphosphene trapped as cycloadduct 5. - Keywords: cyclophosphanes / phosphorus-carbon heterocycles / cleavage of phosphorus-phosphorus bonds / di(aryltelluro) diphosphanes / diphosphene transfer.
Contributions in the Chemistry of Phosphorus, 131. Synthesis and Properties of the Methylenediphosphiranes (t-BuP)2C = CR2 (R = H, Me, 4-ClC6H4)
Baudler, Marianne,Saykowski, Franz,Hintze, Michael,Tebbe, Karl-Friedrich,Heinlein, Thomas,et al.
, p. 1542 - 1550 (2007/10/02)
The first methylenediphoshiranes (diphosphamethylenecyclopropanes) (t-BuP)2C = CH2 (1), (t-BuP)2C = CMe2 (2), and (t-BuP)2C = C(4-ClC6H4)2 (3) were synthesized by cyclocondensation of K(t-Bu)P - P(t-Bu)K with the corresponding 1,1-dichloroolefins.The homocyclophosphanes (t-BuP)n (n = 4,3) and in the case of 1 mainly H(t-Bu)P - P(t-Bu)H are formed as by-products.The three-membered heterocycles 2 and 3 could be purely isolated as surprisingly stable compounds.According to an X-ray single-crystal analysis 3 possesses approximately C2 symmetry and exhibits one of the smallest bonding angles φ (P - P - C) = 52.4 deg on a phosphorus atom experimentally proved so far.Along there are canals filled with disordered n-pentane molecules.
