94012-71-2

Upstream product

• 10297-05-9 1-chloro 4-iodobutane 
• 1066-54-2 trimethylsilylacetylene 
• 91656-99-4 (5-bromo-pent-1-ynyl)-trimehyl-silane 

Downstream Products

• 131353-25-8 dimethyl 2'-(6-(trimethylsilyl)-5-hexynyl)homophthalate 
• 127016-89-1 3-Ethoxy-6-(6-trimethylsilanyl-hex-5-ynyl)-cyclohex-2-enone 
• 137709-42-3 2-(2,5-dimethoxyphenyl)-2-(6-trimethylsilyl-5-hexynyl)-1,3-dithiane 
• 127016-77-7 4-(6-Trimethylsilanyl-hex-5-ynyl)-cyclohex-2-enone 
• 1236880-38-8 (1E)-2-methyl-9-trimethylsilyl-1-phenylnon-1-en-8-yn-3-ol 
• 848312-56-1 (E)-1-phenyl-8-(trimethylsilyl)oct-1-en-7-yn-3-ol 
• 127016-37-9 triphenyl(6-(trimethylsilyl)-5-hexynyl)phosphonium iodide 
• 1092444-48-8 tert-butyl (R)-benzyl-{5-[1-(tert-butyl-dimethylsilyloxy)-9-(6-fluoropyridin-3-yl)-non-2-ylamino]-3-isopropyl-pyrazolo[1,5-a]pyrimidin-7-yl}carbamate 
• 1092444-49-9 tert-butyl benzyl-((R)-5-(9-(6-fluoropyridin-3-yl)-1-hydroxynonan-2-ylamino)-3-isopropylpyrazolo[1,5-a]pyrimidin-7-yl)carbamate 
• 848312-59-4 (1E)-1-phenyloct-1-en-7-yn-3-ol 

Relevant academic research and scientific papers

Reactions of some alkynyl halides with samarium(II) iodide

Certain alkynyl halides (6-halo-1-ynes) react with samarium(II) iodide (SmI2) to give cyclized products (methylenecyclopentanes) in good yield. We have found some interesting evidence for the presence of radical and unstable organosamarium intermediates in these reductive cyclizations. Methyl 7-halohept-2-ynoates are not, however, good substrates for this cyclization methodology.

Allylmetallation of 1-Silylalkynes by 2-(Bromozincmethyl)-2-alkenyl Ethers followed by Pd(0)-catalyzed Cyclization: A one-pot Synthesis of 4-Methylenecyclopentenes

Reaction of 2-(bromozincmethyl)-2-alkenyl ethers 1 a,b,c,d with 1-(trimethylsilyl)-1-alkynes 2 afforded carbometallation products 3, which were converted by Pd(0)-catalyzed cyclization to 4-methylenecyclopentenes 5.The rates of both the addition and cyclization step depend on the concentration of the organozinc compound and the preparation of 5 is best performed using a 1,4-1,8 M solution of 1.At lower concentrations reaction times must be longer and, when 1c is reacted, the addition reaction is incomplete and gives rise to a mixture of products (3 and 14), which on Pd(0)-treatment leads to a mixture of isomeric methylenecyclopentenes (5, 15 and 16). - Key Words: alkyne addition; carbometallation; 2-alkenylzinc compounds; Pd(0)-catalysis; cyclopentenes.