Reaction of „Jordan′s Cation”︁ [Cp₂ZrCH₃(thf)]⁺ with Amino Acid‐Derived Isocyanates—A First Synthetic Route to Oligopeptide‐Modified Group 4 Bent Metallocene Cation Systems

Abstract

Abstract:The organometallic cation [Cp,ZrCH,(thf)]+, employed as the tetraphenylborate salt (l), reacts cleanly in 1 : 1 stoichiomctry with the isocyanates 2 derivcd from valine methyl ester or valylvaline methyl ester, respectively. In each case addition of the Zr-CH, group to the isocyanate sp-carbon center is observed with formation of a functionalized zirconocene cation dcrivative containing a chelating N-metallated N-acetylvaline methyl ester (3 a) or N-acetylvalylvaline methyl ester (3 b) moiety, respectively, co-

Syndiospecific living polymerization of 4-methylstyrene with (trimethyl)pentamethylcyclopentadienyltitanium/tris(pentafluorophenyl)borane/trioctylaluminium catalytic system

“…In order to further evaluate the living polymerization characteristics, the modification of propagation chain end was tested, i. e., the polymerization was performed with Cp*TiMe 3 /B(C 6 F 5 ) 3 /AlOct 3 at -20 8C for 5 min and then terminated with tert-butyl isocyanate 15) . Fig.…”

Bioorganometallic Chemistry - Transition Metal Complexes withα-Amino Acids and Peptides

“…[54 a] The coordination of C,N-protected a-amino acids and peptides to ZrCp 2 fragments is achieved by reaction of [Cp 2 ZrMe(thf)] with OCNCHR 1 COR 2 (82). [55] Cationic compounds of formula [Cp 2 Mo(NH 2 CHRCO 2 )]X (X Cl, PF 6 ) (83) were synthesized some time ago from [Cp 2 MoCl 2 ]. [56] 2.4. a-Amino Acids and Peptides with Organometallic Side Chains…”

Group 4 metallocenes in bioorganometallic chemistry

“…This results in the formation of a metallated N-acyl valinester derivative (30a). The detailed NMR analysis [28] indicated the formation of a typical O,N,O-chelate product. The analogous reaction took place upon treatment of valinylvalinester isocyanate (18b) with ''Jordan's cation'' (10a) [27].…”