515161-06-5

Upstream product

• 515160-93-7 trans-[IrH(PPh₃)2(C(C₆H₅)=CHC(CH₃)O)(acetone)]SbF₆ 
• 10147-11-2 propargyl benzene 
• 3240-11-7 Phenylacetylene-d1 

Relevant academic research and scientific papers

Electronic and steric effects in the insertion of alkynes into an iridium(III) hydride

Insertion of a variety of alkynes into the Ir-H bond of trans-[IrH(PPh 3)2(C(Ph.)=CHC-(O)Me)(acetone)]+ (1) follows three different routes depending on the alkyne structures. For relatively electron-rich alkynes (PhC≡CH, PhCH2C≡CH, and p-OMeC 6H4C≡CH), double insertion occurs stepwise, each alkyne undergoing rearrangement to a vinylidene intermediate independently to afford an iridium(III) η2-butadienyl. In the first alkyne insertion, deuterium labeling and crossover experiments confirm that the alkyne to vinylidene rearrangement is intraligand. Both a vinyl and a vinylidene intermediate were trapped and isolated during this first insertion. In the second alkyne insertion, a C - H agostic intermediate was isolated. Electron-poor alkynes (p-CF3C6H4C≡CH and p-NO2C6H4C≡CH) also undergo double insertion into 1, but deuterium labeling experiments using p-CF 3C6H4C≡CD indicate reversible C(sp)-H oxidative addition. Insertion of highly polarized alkynes (R 1C≡CC(O)R2] to 1 occurs only once and involves no vinylidene intermediates even when R1 = H. The regio- and stereochemistry in this case are mainly controlled by the steric effects of R1. In this series, rare cis-(PPh3)2 intermediates were isolated for HC≡CC(O)R (R = Me or OMe). X-ray crystal structures of representative products are reported.

A rare η2-butadienyl complex from an alkyne double insertion with double vinylidene rearrangement

A rare η2-butadienyl Ir(III) complex with a weak Ir...C bond is formed from 1-alkyne double insertion with the independent double alkyne to vinylidene rearrangement. A reaction intermediate is isolated, and labeling and crossover experiments indicate the intramolecularity of both alkyne to vinylidene rearrangements. Copyright