Carbonyl Allenylations andPropargylations by 3-Chloro-1-propyne or 2-Propynyl Mesylateswith Tin(IV) Chloride and Tetrabutylammonium Iodide
作者:Yoshiro Masuyama、Akiko Watabe、Yasuhiko Kurusu
DOI:10.1055/s-2003-41012
日期:——
By the use of tin(IV) chloride and tetrabutylammonium iodidein dichloromethane, 3-chloro-1-propyne or 2-propynyl mesylate canbe applied to allenylation and propargylation of aldehydes (carbonylallenylation and propargylation) to produce a mixture of 1-substituted2,3-butadien-1-ols and 1-substituted 3-butyn-1-ols. 1-Substituted2-propynyl mesylates selectively cause carbonyl propargylation,while 3-substituted 2-propynyl mesylates cause carbonyl allenylation.
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, tetrabutylammoniumiodide 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
On the use of 3-bromopropyne as a reagent for the introduction of the pyruvate moiety
作者:Chen Chen、David Crich
DOI:10.1039/c39910001289
日期:——
In the presence of metallic zinc 3-bromopropyne reacts with aldehydes to give homopropynylic alcohols which are converted to the corresponding bromohomopropynylic acetates by acetylation followed by reaction with N-bromosuccinimide and a catalytic quantity of silver acetate; these derivatives are then oxidized to γ-acetoxy-α-ketoesters with osmium tetroxide and tert-butyl hydroperoxide resulting in a convenient four step sequence for the introduction of the pyruvate moiety.
One-Pot, Regioselective Synthesis of Homopropargyl Alcohols using Propargyl Bromide and Carbonyl Compound by the Mg-mediated Reaction under Solvent-free Conditions
in organic synthesis is the most important goal in “Green” chemistry. We report a simple, efficient and facile method for the addition of progargyl bromide to carbonyl compounds using Mg metal as a mediator undersolvent-freeconditions which could regioselectively generate homopropargyl alcohols efficiently in good to excellent yields. The procedure has advantages such as short reaction time, operationally
Barbier-type propargylation of carbonyl compounds with propargyl bromide has been achieved with reactive zinc–copper couple under solvent-free conditions. The reaction of aldehydes with propargyl bromide produced the unique homopropargyl alcohols in excellent yields at room temperature without the formation of homoallenyl alcohols. The ketones reacted with propargyl bromide to give the corresponding homopropargyl