747-58-0

Upstream product

• 5471-63-6 1,3-diphenylisobenzofuran 
• 76911-01-8 5-hexynyl p-toluenesulfonate 
• 103670-61-7 (dibromomethylene)cyclopentane 
• 878191-46-9 1,2,5,6-tetraaza-dispiro[2.0.2.4]deca-1,5-diene 
• 878191-43-6 1,2,5,6-tetraaza-dispiro[2.0.2.4]decane 
• 108-94-1 cyclohexanone 
• 80522-46-9 1-triisopropylsiloxy-1-cyclohexene 
• 62791-22-4 tert-butyl(cyclohex-1-en-1-yloxy)dimethylsilane 
• 4342-22-7 1-(triethylsilyloxy)cyclohexene 

Downstream Products

• 101749-41-1 9a,10-Diphenyl-1,3,4,9a-tetrahydro-2H-anthracen-9-one 
• 97255-61-3 9,10-diphenyl-1,2,3,4-tetrahydroanthracene 

Relevant academic research and scientific papers

One-Pot Synthesis of Silylated Enol Triflates from Silyl Enol Ethers for Cyclohexynes and 1,2-Cyclohexadienes

Regiocontrolled synthesis of precursors for strained cyclohexynes and 1,2-cyclohexadienes is described based on one-pot rearrangement of silyl enol ether followed by formation of enol triflate. Treatment of silyl enol ether with a combination of LDA and tBuOK led to the migration of the silyl group to generate α-silyl enolate, which was treated with Comins' reagent to provide the corresponding enol triflate. The transient α-silylated lithium enolate was smoothly isomerized in the presence of stoichiometric amount of water within one hour at room temperature, providing precursors for cyclohexynes exclusively in one pot. Effects of silyl groups, isomerization of the lithium enolate, and regiocontrolled generation of these precursors for these strained molecules were also investigated.

Generation of cycloalkynes through deprotonation of cyclic enol triflates with magnesium bisamides

Deprotonative generation of cyclohexynes, cycloheptynes, and cyclooctynes was achieved by controlling the reactivities of transient anionic species from the corresponding enol triflates with magnesium bis(2,2,6,6-tetramethylpiperidide) as a base. The star

Bi-3H-diazirin-3-yls as precursors of highly strained cycloalkynes

(Chemical Equation Presented) No reagents and very mild conditions are required for the transformation of isolable precursors 3 into highly strained cycloalkynes 4 (cycloheptyne, cyclohexyne, norbornyne), which can be trapped by cycloaddition reactions.

Generation of cycloalkylidene carbenes via exo-type cyclization of alkynyllithiums bearing remote leaving group

The reaction of 5-hexynyl rosylate (3a) with alkynyllithium (RC≡CLi; R = Ph, TMS) gives enynes 5 and 6. The reaction proceeds through a mechanism involving a novel exo-type cyclization of 6-lithio-5-hexynyl tosylate to form cyclopentylidene carbene. Enyne 6 is produced by the addition of RC≡CLi to the carbene, whereas rearrangement of the carbene to cyclohexyne followed by carbolithiation with RC≡CLi gives enyne 5. The formation of cyclopentylidene carbene and cyclohexyne as intermediates is clearly demonstrated by trapping experiments with cyclohexene (and triethylsilane) and with 1,3- diphenylisobenzofuran, respectively. Alkynyllithiums derived from 3-butynyl and 6-heptynyl p-fluorobenzenesulfonates (19a,b) undergo a similar exo-type cyclization to give cyclopropylidene and cyclohexylidene carbenes, respectively.

Cyclohexynes as intermediates in a novel endo-cyclization of alkynylzincates derived from 5-hexynyl tosylates

The n-type endo-cyclization of metal acetylides to form cyclohexynes was observed for the first time in the reaction of alkynylzincates derived from 5-hexynyl tosylates. The endo-cyclization took place in competition with erocyclization, leading to the formation of 1-(cyclopentylidene)alkylzincs.