Molybdenum hexafluorophosphate

The retrosynthetic analysis of the 2-oxygenated carbazole alkaloids, 2-methoxy-3-methylcarbazole (37), O-methylmukonal (glycosinine) (38), 2-hydroxy-3-methylcar-bazole (52), and mukonal (53) based on the molybdenum-mediated approach led to the molybdenum-complexed cation (663) and 3-methoxy-4-methylaniline (655) as precursors (Scheme 5.51). The cationic molybdenum complex, dicarbonyl (ri -cyclohexadiene)(r -cyclopentadienyl)molybdenum hexafluorophosphate (663), required for the electrophilic substitution, was easily prepared quantitatively through known literature procedures (586,587). 

We reported the first total synthesis of l,T-bis(2-hydroxy-3-methylcarbazole) (213) using our molybdenum-mediated construction of the carbazole framework (560). The required monomer, 2-hydroxy-3-methylcarbazole (52), was obtained in three steps, and 22% overall yield, starting from dicarbonyl(ri -cyclohexa-l,3-diene)(ri -cyclopentadienyl)molybdenum hexafluorophosphate (663) and 3-meth-oxy-4-methylaniline (655) (560) (see Scheme 5.52). Finally, oxidative coupling of the monomer 52 using p-chloranil afforded l,T-bis(2-hydroxy-3-methylcarbazole) (213) in 38% yield (560) (Scheme 5.167). 

FjFeMoOjP2C34H2g, Iron(l+), p-acetyl-2k C lK0-tetracarbonyl-lK C,2K C-bis[ 1,2-(Ti -cyclopentadienyl)l(tri-phenylphosphine-licP)molybdenum-, hexafluorophosphate(l-), 26 241 FjFeMoOgPCijHij, lron(l+), p-acetyl-2K-C icO-pentacarbonyl-li C,2K C-bisl 1,2-(tl -cyclopentadienyl)]molybdenum-, hexafluorophosphatefl—), 26 239 FgFe02PC, H j, Iron(l+), (ii -cyclopenta-dienyl)dicarbonyl(tetrahydrofuran)-, hexafluorophosphatefl—), 26 232 F4Fe204P2CjjH28, lron(l+), p-acetyl-2K-C 1 KO-tricarbonyl-1 x, 2KC-bis [ 12-(il -cyclopentadienyl))(tripheiiylphos-phine-2icP)di-, hexafluorophos-phate(l-), 26 237... 

OjFjFeSjCgHj, Iron(l-t-), dicaibonyl(Ti -cyclopentadienylXthiocarbonyl)-, tii-fluoromethanesulfonate, 28 186 OsFgFeMoP2C34H2g, Iron(l +X p-acetyl-2icC -lKO-tetracarbonyl-lK C,2K C-bis( 12 (tl "cyclopentadienyl)l(tri-phenylphosphine-1 KP)molybdenum-, hexafluorophosphate(l—), 26 241 OjFgFejPCioHij, Iron(I+), ti-acetyl-C 0-bis(dicarbonyl(Ti-cyclopentadienyl)-, hexafluorophosphate(l—), 26 235 OjHReCj, Rhenium, pentacarbonyl-hydrido-, 26 77... 

OjFjFeS2C9Hj, Iron(l +X dicarbonyl( f -cyclopentadienyl) (thiocarbonyl)-, tri-fluoTometbanesulfonate, 28 186 OjF6FeMoP2C34H28, Iron(l -h), /i-acetyl-2icC licO-tetracarbonyl-lK C,2ic C-bis[l, 2-(q -cyclopentadienyl) ] (triphenylphosphine-1 icP)molybdenum-, hexafluorophosphate(l —), 26 241 OjF4Fe2PC,oH,3, Iron(l +), /i-acetyl-C 0-bis[dicarbonyl(ij-cyclopentadienyl)-, hexafluorophosphate(l —X 26 235 OjHReC, Rhenium, pentacarbonylhy-drido-, 26 77... 

F7Mo02PsC34H4B, Molybdenum(II), dicar-bonylbis[ 1,2-ethanediylbis(diphenyl-phosphine)]fluoro-hexafluorophosphate(l -), 26 84... 

The (IsQ-coordinated species [Mo(CO)3(py)3] prepared from [Mo(CO)6] and pyridine is useful for the synthesis of various jr-allyl molybdenum compounds (68JOM(13)Pl, 970M5365). The 3-allyl complexes [( 3-allyl)Mo(CO)2Br(py)2] form [( 3-allyl)Mo(CO)2(S,S)(py)] with the anionic S,S-donors, dithiocarbamates and xanthates of sodium and potassium, M (S,S) (81JOM(218)185). [( 3-C3H5)Mo(CO)2(py)2Br] (68JO M(14)375) with thallium hexafluorophosphate in acetonitrile gives... 

Tris(acetonitrile)dicarbonyl(i -l,2,3-triphenylcyclopropenyl)molybdenum(I) Hexafluorophosphate (15, X = PFj) Typical Procedure ... 

Standard borohydride reductions were successfully realized for pyranoic ligand conversions in some optically active molybdenum-coordinated compounds. For example, hexafluorophosphate 190 (R = EtO) gave the corresponding neutral species 191 (R = EtO) in 94% yield. Analogous transformations were accomplished with other / -substituted salts 190 (93JA891). 

After hydrolysis of the anion of Tc(C6Hf,)2j[AlCl4], the cation was precipitated as hexafluorophosphate. The yellow-green, diamagnetic complex salt is stable in air, acids and bases [617]. Prior to the preparation of ponderable amounts, the cation was produced by irradiating h/A(benzene)molybdenum with thermal neutrons ... 

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