Reactivity and isomerization of tert-butyldiallylphosphine with Os3 metallic cluster: Insights into the reaction mechanism and plausible intermediates through spectroscopic evidence and computational calculations

Abstract:

The reaction of tert‑butyldiallylphosphine with [Os<inf>3</inf>(CO)<inf>10</inf>(CH<inf>3</inf>CN)<inf>2</inf>] give the compounds [Os<inf>3</inf>(CO)<inf>11</inf>{κ(P)-^tBuP(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)<inf>2</inf>}] 1a, [Os<inf>3</inf>(CO)<inf>11</inf>{κ(P)-^tBuP(CH[dbnd]CHCH<inf>3</inf>)<inf>2</inf>}] 1b, [Os<inf>3</inf>(CO)<inf>10</inf>{κ(P)-^tBuP(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)<inf>2</inf>}<inf>2</inf>] 2, diastereoisomers [Os<inf>3</inf>(CO)<inf>10</inf>{µ:η²-κ³(P,C²,C³)-^tBuP(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)<inf>2</inf>}] (3a Sp, 3b Rp) and [Os<inf>3</inf>(CO)<inf>9</inf>{µ:η²-κ³(P,C²,C³)-^tBuP(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)<inf>2</inf>)(κ(P)-^tBuP(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)<inf>2</inf>}] (4a Sp, 4b Rp). Thermolysis of 2 or 3 gave the complexes [Os<inf>3</inf>(CO)<inf>8</inf>(μ-H){μ<inf>3</inf>:η¹:η²:η²-κ⁵(P,C²,C³,C⁵,C⁶)-P(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)(CH<inf>2</inf>C[dbnd]CH<inf>2</inf>)}] 5 and diastereoisomers [Os<inf>3</inf>(CO)<inf>8</inf>(µ-H)<inf>2</inf>{µ<inf>3</inf>:η¹:η¹:η²-κ³(P,C²,C³)-^tBuP(CH<inf>2</inf>CH[dbnd]CH<inf>2</inf>)(C[dbnd]CHCH<inf>2</inf>)}] (6a Sp, 6b Rp). 1a, 1b, 3a, 5 and 6a which were characterized by X-ray analysis. To the best of our knowledge, 1b is the first characterized structure involving isomerization of the double bond of the allylic substituent at room temperature in the case of metallic clusters. X-ray coordinates were used to study the possible reaction mechanisms through computational calculations at the MN15L/def2svp level of theory, obtaining good agreement between experimental and computational results.

Año de publicación:

2024

Keywords:

• Allylphosphines
• DFT calculations
• Diastereoisomers
• Isomerization
• Trimetallic clusters

Fuente:

scopus