Synthesis and selective silylation of ω-hydroxy functionalized (η2-alkenyl)carbene complexes of chromium(0) and tungsten(0) Part 11. The chemistry of metallacyclic alkenylcarbene complexes

Nanostructured Thin Films Obtained from Fischer Aminocarbene Complexes

“…This behavior is presumably due to the bulkiness of the Fc residue, which has a steric repulsion with the side-chain, as observed in other ferrocenyl amino carbenes analogues [ 30 ]. In the case of 4 ( a-b ) complexes, they exist as mixtures of Z - and E -isomers with regard to the partial C-N double bound, being the isomer E the main specie, in accordance with the literature [ 31 ].…”

Syntheses, structures and electrochemistry of some 1-(η2-allylamino)-1-ferrocenylcarbene complexes of chromium(0), molybdenum(0) and tungsten(0)

“…At room temperature complexes 2 and 3 actually exist as mixtures of Z-and E-isomers with regard to the partial C-N double bond. Interestingly, and contrary to the analogous 1-alkyl or 1-aryl substituted aminocarbene complexes [21], the Z-isomers prevail by far with ratios ranging from 6:1 to 11:1 for complexes 2 and with the E-isomer of 3 not being detectable at all. This is presumably due to the bulkiness of the Fc residue.…”

“…Complexes of types 2 and 3 were prepared by aminolysis at room temperature of the respective 1-methoxy-1-ferrocenylcarbene complexes (OC) 5 M@C(OMe)Fc (1) (M = Cr: 1a; Mo: 1b; W: 1c) with either a 10-fold excess of allylamine in Et 2 O or a 4-fold excess of 1-aminobut-(2Z)-en-4-ol in THF, respectively, as described previously for similar 1-alkyl-1-allylaminocarbene complexes by us [21] and for the same 1-ferrocenyl-1-allylaminocarbene complexes 2a-c very recently by the Rudler group [19] (Scheme 1). The required starting complexes 1 were obtained, according to a modified procedure by Connor and Lloyd [17], from the appropriate metal hexacarbonyls M(CO) 6 , monolithioferrocene, and Meerwein salt Me 3 O þ BF À 4 in ca.…”

“…doi:10.1016/j.jorganchem.2005. 10.047 established method [20,21]. We also took a closer look at the Z/E ratios of the uncoordinated precursor complexes which are crucial for the yield of the photo-chelation step.…”

Synthesis of new heterocycle-based selenoamides as potent cytotoxic agents

“…In most cases, the E stereoisomer is the major species, which agrees with the behavior reported for similar carbene complexes. 28,[32][33] However, for 2h, the Z stereoisomer is the only species, 13 as result of the steric interaction between the ferrocenyl group and the hydroxyalkyl chain.…”