Superfast Formation of C(sp 2 )-N, C(sp 2 )-P, and C(sp 2 )-S Vinylic Bonds in Water Microdroplets.

We report examples of C(sp 2 )-N, C(sp 2 )-S, and C(sp 2 )-P bond-forming transformations in water microdroplets at room temperature and atmospheric pressure using N 2 as a nebulizing gas. When an aqueous solution of vinylic acid and amine is electrosprayed (+3 kV), the corresponding C(sp 2 )-N product is formed in a single step, which was characterized using mass spectrometry (MS) and tandem mass spectrometry (MS 2 ). The scope of this reaction was extended to other amines and other unsaturated acids, including acrylic (CH 2 =CHCOOH) and crotonic (CH 3 CH=CHCOOH) acids. We also found that thiols and phosphines are viable nucleophiles, and the corresponding C(sp 2 )-S and C(sp 2 )-P products are observed in positive ion mode using MS and MS 2 .