Chapter 12, Problem 17P

The IR (infrared) spectra of two pure compounds (0.010 M compound A in solvent and 0.010 M compound B in solvent) are given. The pathlength of the cell is 1.00 cm. The y-axis in the spectra is transmittance rather than absorption, so that the wavenumbers at which there is a dip in the curve correspond to absorption peaks. A mixture of A and B in unknown concentrations gave a percent transmittance of 49.8% at 2976 cm¹ and 44.9% at 3030 cm-1 Wavenumber 0.010 M A 0.010 M B Unknown 3030 cm-1 35.0% 93.0% 44.9% 2976 cm-¹ 76.0% 42.0% 49.8% What are the concentrations of A and B in the unknown sample? Transmittance (%) 100 90 80 70 60 50 40 2976 cm-1 30 3030 cm-1 20 Pure A 10 Pure B 0 3040 2990 Wavenumber (cm-1) 2940 2890

synthesize 1-propyne starting with propane.

starting reactant IV target + enantiomer 1) BH3, THF 2) H₂O2, NaOH, H₂O 1) Hg(OAc)2, THF, H₂O (or ROH) 2) NaBH4 D2, Pt/C H₂, Pt/C D2, Lindlar catalyst or Ni₂B H₂, Lindlar catalyst or Ni₂B NaNH, OH/H₂O or SH/H₂S H₂O/H₂O 1) 03 2) H₂O 1) 03 2) (CH3)2S HBr, w/ROOR HBr, (cold, dark, no ROOR) Naº, NH3(e) NBS (trace Br2), light HgSO4, H2SO4, H₂O Naº, ROH 1) Sia₂BH, THF 2) H2O2, NaOH, H₂O H3O/ROH or H₂O*/RSH OR/ROH or SR/RSH 1) OsO4, NMO 2) NaHSO3, H₂O 1) MCPBA (peroxy acid) 2) H3O, H2O (or ROH or RSH) KMnO4 (warm, concentrated) Br₂/H₂O Br₂, heat or light Br2, cold, dark, no peroxides (CH3)3CO(CH3)3COH ROH or RSH H₂O KMnO4/OH (cold, dilute)