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2. Reaction of Ruz(CO 2 in refluxing heptane with freshly distilled cyclopentadiene affords a pale yellow solution of A. Carbon monoxide is evolved in the course of this reaction. Data for A: IR: 2025, 1965 cm'; 'H NMR of an aliquot: 85.21, s, 5H; -11.5, s, 1H. Attempts to isolate A lead to formation of [(-CsHz)Ru(CO)2]2 Addition of PMe3 (excess) to solution A followed by brief heating forms B (with evolution of more CO), which was isolated by removal of solvent and vacuum sublimation onto a water cooled probe. Compound B is a pale yellow crystalline solid. Data for B: IR: 1931 cm '; 'H NMR: (CD-C12, 8) 4.99, s, 5H; 1.49, d, 9H, J = 10 Hz; -12.6, d, 1H, J-35 Hz. Anal: C 39.9; H 5.6% Identify A and B, C. Give electron counts and justify your choices in terms of the data given. 2. Reaction of Ruz(CO 2 in refluxing heptane with freshly distilled cyclopentadiene affords a pale yellow solution of A. Carbon monoxide is evolved in the course of this reaction. Data for A: IR: 2025, 1965 cm'; 'H NMR of an aliquot: 85.21, s, 5H; -11.5, s, 1H. Attempts to isolate A lead to formation of [(-CsHz)Ru(CO)2]2 Addition of PMe3 (excess) to solution A followed by brief heating forms B (with evolution of more CO), which was isolated by removal of solvent and vacuum sublimation onto a water cooled probe. Compound B is a pale yellow crystalline solid. Data for B: IR: 1931 cm '; 'H NMR: (CD-C12, 8) 4.99, s, 5H; 1.49, d, 9H, J = 10 Hz; -12.6, d, 1H, J-35 Hz. Anal: C 39.9; H 5.6% Identify A and B, C. Give electron counts and justify your choices in terms of the data given