60186-80-3

Upstream product

• 110211-20-6 Acetic acid 1-hexyl-hept-2-ynyl ester 
• 122471-92-5 ((Z)-1-Butyl-non-1-enylselanyl)-benzene 
• 629-06-1 1-Chloroheptane 
• 693-02-7 hex-1-yne 
• 629-04-9 1-Bromoheptane 
• 86409-85-0 (E)-2-(phenylseleno)-1-(p-tolylsulfonyl)-1-decene 
• 122471-78-7 1-Methyl-4-((Z)-2-phenylselanyl-dec-2-ene-1-sulfonyl)-benzene 

Relevant academic research and scientific papers

Alkylation of 1-alkynes in THF

Alkynes may be easily alkylated by sequential treatment with n-BuLi followed by an alkyl halide in THF. Primary iodides give excellent yields (75-99%) as do bromides in the presence of catalytic amounts of Bu4NI or NaI; in the absence of an iodide source, bromides react poorly. This method offers advantages over existing methods which use HMPA or NH3 as co-solvents.

Preparation of Allenic Sulfones and Allenes from the Selenosulfonation of Acetylenes

β-(Phenylseleno)vinyl sulfones 2 are readily obtained from the free-radical selenosulfonation of acetylenes.Compounds 2 isomerize to allyl sulfones 4 under base-catalyzed conditions in nearly quantitative yield, with high stereoselectivity favoring the Z configuration.Allyl sulfones 4 afford generally high yields of allenic sulfones 1 when subjected to oxidation with m-chloroperbenzoic acid or tert-butyl hydroperoxide, followed by selenoxide syn-elimination.The sulfone-stabilized anion intermediates in the isomerizations of 2 to 4 can be alkylated, deuterated,or silylated in the α-position prior to oxidation, providing allenic sulfones with an additional α-substituent.In some cases, spontaneous elimination of the phenylseleno group occurred, producing the allenic sulfone without the need for an oxidation step.Desulfonylation of allyl sulfones 4f, 4c, and 25 with sodium amalgam afforded vinyl selenides that were converted to allenes in moderate to good yields by oxidation-elimination.The copper catalyzed coupling of allyl sulfones 4 with Grignard reagents comprises an alternative route to vinyl selenide precursors of allenes.These procedures permit the synthesis of various α- and γ-substituted allenic sulfones and allenes from acetylenes.

PALLADIUM-CATALYZED REDUCTION OF PROPARGYLIC ACETATES WITH SmI2. A MILD AND CONVENIENT METHOD FOR THE PREPARATION OF ALLENES

A highly regioselective reduction of propargylic acetates has been attained by using SmI2 and catalytic Pd(0) in the presence of 2,4-dimethyl-3-pentanol affording various types of allenes in high yields.