Integrating the Data — practice questions

A compound has a molecular ion at m/z 46, an IR with a broad absorption at 3350 cm⁻¹ and no peak near 1700 cm⁻¹, and a single ¹³C signal region showing two signals at 18 and 58 ppm. Identify the molar mass, the functional group and the number of carbon environments.

Determine the structure of a compound with a molecular ion at m/z 58, an IR showing a strong absorption at 1715 cm⁻¹ and nothing above 3000 cm⁻¹ except C–H, and two ¹³C signals at 31 and 207 ppm.

A compound gives a molecular ion at m/z 78 and an M+2 peak at m/z 80 of about one third the height. Its IR shows C–H just below 3000 cm⁻¹ and nothing above 3000 or near 1700 cm⁻¹. Its ¹³C spectrum shows one signal at 25 ppm. Justify the structure fully, integrating all three techniques.