Integrated Chemical Process: One-Pot Double Elimination Method for Acetylenes

Abstract

A novel one-pot process for synthesis of acetylenes has been achieved in which the following series of steps are integrated: addition of an a-anion of sulfone to aldehyde, trapping of the resulting adduct to incorporate a leaving group, and double elimination of this intermediate. Consolidation of Peterson elimination renders the process much simpler. This method provides a convenient and high-yielding access to a variety of enynes and polyynes as well as to functionally substituted aryl acetylenes containing halogen(s) or acetal groups, which are useful building blocks for aryl acetylene scaffolds. Iteration of the one-pot generation of acetylenic bonds provides a new methodology for the buildup of aryl acetylene skeletons.

Transition Metal‐Free One‐Pot Protocol Toward Conjugated Arylbutadiynyl Sulfides

“…Different from the previous protocols, different S-ethyl 3-oxo-3-aryl-propanethioates 1f-1j were also tested under the optimal conditions, leading to the desired arylbutadiynyl ethyl sulfides 2f-2j successfully in moderate to good yields from 76 to 87% (Table 2, entries 6-10). Except for the S-alkyl-3-oxo-3-aryl-propanethioates, S-aryl-3-oxo-3-aryl-propanethioates reacted well, yielding the corresponding phenyldialkynyl-S-phenyl sulfides in yields from 75 to 89% (Table 2, entries [11][12][13][14][15].…”

“…Under this background, Otera group disclosed another approach, applying a double-elimination protocol toward polyenes or acetylenes. [12] Inspired by the fruitful results, our group has disclosed a transformation of methylthiomethyl phenyl sulfone (MP-S) toward diakynyl sulfides. [13] However, there are still some limitations: (1) the formation of the products relied largely on the aldehyde components, (2) uncommon substrate MP-S was involved, and (3) a limited scope of the substrates; only methyl sulfides were obtained from the system.…”

Base‐Induced One‐Pot Preparation of N‐ or P‐Substituted Alkynes

“…IR (neat): ν = 3054, , 1005, 741 cm -1 . MS (EI): m/z (%) = 77 (3.5), 88 (5), 102 (3), 127 (11), 255 (57), 318 (4), 381 (12), 283 (2.5), 410 (100)…”

“…Methylthiomethyl phenyl sulfone (MP-S) was then introduced into the transformation of aldehydes towards sulfur-substituted acetylenes. [12] Still, the special reagent MP-S restricted the methodology for general applications. As a continuation of our long-standing interest in the formation of sulfur-or selenium-substituted alkynes, [13] we wish to demonstrate herein a facile transformation of nitrogen-or phosphine-substituted acetylenes from easily-prepared starting materials (Scheme 1).…”

Integrated Chemical Process. Convergent Strategy forortho-Phenylene Ethynylene Skeleton by One-Pot Double Elimination Method

“…7 In this protocol, double elimination is a key step, where consecutive eliminations of phosphate and phenyl sulfinate on protected aldol II furnish 2a via vinyl sulfone III (Equation). Successive treatment of acetal sulfone 1 with BuLi, aldehyde, diethyl chlorophosphate and t-BuOK is effective for access to large conjugated skeletons.…”