Carbonyl propargylation by 1-substituted prop-2-ynyl mesylates and carbonyl allenylation by 3-substituted prop-2-ynyl mesylates with tin(II) iodide and tetrabutylammonium iodide

1-Substituted prop-2-ynyl mesylates cause propargylation of aldehydes with tin(II) iodide, tetrabutylammonium iodide and sodium iodide in 1,3-dimethylimidazolidin-2-one to produce 2-substituted but-3-yn-1-ols, while 3-substituted prop-2-ynyl mesylates cause allenylation of aldehydes under the same conditions as those of the propargylation by 1-substituted prop-2-ynyl mesylates to produce 2-substituted buta-2,3-dien-1-ols.