Synthesis and Characterization of Free and Coordinated 1,2,3-Tripnictolide Anions

We have investigated the chemical reactivity of heptaatomic anionic clusters of the group 15 elements ([E₇]^3–/[HE₇]^2–, E = P, As) toward the symmetric and asymmetrically substituted alkynes diphenylacetylene and phenylacetylene. The results reported herein, alongside a previous report on the reactivity of such clusters toward acetylene, describe a versatile route by which to access otherwise elusive 1,2,3-tripnictolide anions of the general formula [E₃C₂RR′]⁻ (R = R′ = H, E = P (<b>1</b>), As (<b>2</b>); R = R′ = C₆H₅, E = P (<b>3</b>) As (<b>4</b>); R = H, R′ = C₆H₅, E = P (<b>5</b>), As (<b>6</b>)). These species can be isolated as [K­(18-crown-6)]⁺ or [K­(2,2,2-crypt)]⁺ salts. All anions were characterized by multielement NMR spectroscopy and electrospray mass spectrometry. In addition, single-crystal X-ray diffraction structures of the novel species [K­(18-crown-6)­(THF)₂]­[<b>3</b>], [K­(2,2,2-crypt)]­[<b>4</b>]·<i>x</i>THF (<i>x</i> = 0, 0.5), and [K­(18-crown-6)­THF]­[<b>6</b>] were also obtained. The chemical reactivity of these group 15 cyclopentadienyl analogues has been explored in a series of ligand displacement reactions with Mo­(CO)₃(L)₃ (L = CO, CH₃CN) to yield the complex anions [(η⁵-E₃C₂H₂)­Mo­(CO)₃]⁻ (E = P (<b>7</b>), As (<b>8</b>)), [{η⁵-E₃C₂(C₆H₅)₂}­Mo­(CO)₃]⁻ (E = P (<b>9</b>), As (<b>10</b>)), and [{η⁵-E₃C₂H­(C₆H₅)}­Mo­(CO)₃]⁻ (E = P (<b>11</b>), As (<b>12</b>))

Synthesis and Characterization of Free and Coordinated 1,2,3-Tripnictolide Anions

We have investigated the chemical reactivity of heptaatomic anionic clusters of the group 15 elements ([E₇]^3–/[HE₇]^2–, E = P, As) toward the symmetric and asymmetrically substituted alkynes diphenylacetylene and phenylacetylene. The results reported herein, alongside a previous report on the reactivity of such clusters toward acetylene, describe a versatile route by which to access otherwise elusive 1,2,3-tripnictolide anions of the general formula [E₃C₂RR′]⁻ (R = R′ = H, E = P (<b>1</b>), As (<b>2</b>); R = R′ = C₆H₅, E = P (<b>3</b>) As (<b>4</b>); R = H, R′ = C₆H₅, E = P (<b>5</b>), As (<b>6</b>)). These species can be isolated as [K­(18-crown-6)]⁺ or [K­(2,2,2-crypt)]⁺ salts. All anions were characterized by multielement NMR spectroscopy and electrospray mass spectrometry. In addition, single-crystal X-ray diffraction structures of the novel species [K­(18-crown-6)­(THF)₂]­[<b>3</b>], [K­(2,2,2-crypt)]­[<b>4</b>]·<i>x</i>THF (<i>x</i> = 0, 0.5), and [K­(18-crown-6)­THF]­[<b>6</b>] were also obtained. The chemical reactivity of these group 15 cyclopentadienyl analogues has been explored in a series of ligand displacement reactions with Mo­(CO)₃(L)₃ (L = CO, CH₃CN) to yield the complex anions [(η⁵-E₃C₂H₂)­Mo­(CO)₃]⁻ (E = P (<b>7</b>), As (<b>8</b>)), [{η⁵-E₃C₂(C₆H₅)₂}­Mo­(CO)₃]⁻ (E = P (<b>9</b>), As (<b>10</b>)), and [{η⁵-E₃C₂H­(C₆H₅)}­Mo­(CO)₃]⁻ (E = P (<b>11</b>), As (<b>12</b>))