822-93-5

Usage

Synthesis

Methyltriphenylphosphonium bromide (11.6 g, 32.4 mmoles) was weighed into a dry, 250 mL three neck, round bottom flask, and 50 mL of dry THF (distilled from Na/benzophenone) was cannulated into the reaction vessel. A positive pressure of argon was maintained throughout the reaction. The suspension was cooled to 0-5 ℃, and n-butyllithium, 2.5 M in hexane (14.0 mL, 32.4 mmoles) added dropwise from an addition funnel to the well-stirred solution. A yellow color developed upon addition of the base, indicative of formation of the Wittig reagent.Dicyclopropyl ketone (1) (3.5 mL, 32.4 mmoles), cooled to O℃, a bottle with vacuum distilled dicyclopropyl ketone was kept in ice-water bath for 30 minutes, then (1) was added dropwise to the Wittig reagent. The color changed from yellow to off-white once the addition was complete. The mixture was allowed to warm slowly to room temperature. The reaction mixture was stirred overnight under a positive pressure of argon. After 24 hr, the reaction mixture was extracted successively with 25 mL of water and 25 mL of saturated NaCI solution. The organic layer was dried over anhydrous MgSO4. The solvent was removed by fractional distillation using a short Vigreux column, and the residue analyzed by gas chromatography (Hewlett Packard 5890, using a DB-5 column, FID detector, 30 m length, 0.53 mm id). The reaction mixture consisted of 1,1-dicyclopropylethylene (2) (80%), unreacted dicyclopropyl ketone (10%), and unidentified compounds (10%). Triphenylphosphine oxide (3) was the primary byproduct .

Upstream product

• 18895-50-6 dicyclopropylmethylcarbinol 
• 19493-09-5 Methylenetriphenylphosphorane 
• 1121-37-5 dicyclopropyl ketone 
• 1779-49-3 Methyltriphenylphosphonium bromide 
• 186581-53-3 diazomethane 
• 27567-82-4 bicyclopropylidene 
• 79521-21-4 C₈H₁₁⁽²⁾H 
• 79521-26-9 1-methyl-1-cyclopropyl-3-lithiomethylenecyclopropane 
• 74-95-3 1,1-dibromomethane 

Downstream Products

• 23772-96-5 1,2-Dicyclopropyl-2-phenylaethylen 
• 38662-41-8 (2-Cyclopropyl-2-cyclopropylidene-ethyl)-benzene 
• 23772-87-4 2,2-dicyclopropylacetaldehyde 
• 54159-43-2 1,1-Diphenyl-3-cyclopropylhexa-1,3-dien 
• 54159-42-1 1,1-Dicyclopropyl-2,2-diphenylcyclopropane 
• 123316-46-1 2-chloro-3,3-dicyclopropylcyclobutanone 
• 136847-54-6 3,3-Dicyclopropyl-1,2,4-trioxolan 
• 136847-60-4 C₁₁H₁₆O₂ 
• 136847-61-5 3,3,6,6-Tetracyclopropyl-1,2,4,5-tetroxan 
• 1121-37-5 dicyclopropyl ketone 
• 10027-72-2 methoxymethyl hydroperoxide 
• 136847-59-1 3,3-Dicyclopropyl-1,2-dioxolan 
• 83735-98-2 2-phenyl-3-phenylcarbamoyl-5,5-dicyclopropylisoxazolidine 
• 112641-89-1 2,2-dichloro-3,3-dicyclopropylcyclobutanone 

Relevant academic research and scientific papers

B(C6F5)3-Catalyzed Hydrosilylation of Vinylcyclopropanes

A hydrosilylation of vinylcyclopropanes (VCPs) catalyzed by the strong boron Lewis acid B(C6F5)3 is reported. For the majority of VCPs, little or no ring opening of the cyclopropyl unit is observed. Conversely, for VCPs with bulky R groups, such as ortho-substituted aryl rings or branched alkyl residues, ring opening is the exclusive reaction pathway. This finding is explained by the thwarted hydride delivery to a sterically shielded, β-silicon-stabilized cyclopropylcarbinyl cation intermediate.

Visible light-mediated intermolecular [2 + 2] photocycloaddition of 1-aryl-2-nitroethenes and olefins

Despite the importance of cyclobutanes there are not many direct [2 + 2] photocycloaddition reactions which can be performed with visible light in the absence of a catalyst. A notable exception is the reaction of 1-aryl-2-nitroethenes and olefins which can be performed at a wavelength of λ = 419 nm or λ = 424 nm in CH2Cl2 as the solvent. In the present study, a total of 15 1-aryl-2-nitroethenes were found to undergo a [2 + 2] photocycloaddition with 2,3-dimethyl-2-butene (28-86% yield) and a set of 12 olefins was studied in their photocycloaddition to 1-phenyl-2-nitroethene (37-88% yield). All mechanistic results are in agreement with a triplet reaction pathway and with the intermediacy of a 1,4-diradical.

Repairing the thiol-ene coupling reaction

Thiol-ene coupling (TEC) reactions emerged as one of the most useful processes for coupling different molecular units under reaction mild conditions. However, TEC reactions involving weak C-H bonds (allylic and benzylic fragments) are difficult to run and often low yielding. Mechanistic studies demonstrate that hydrogen-atom transfer processes at allylic and benzylic positions are responsible for the lack of efficiency of the radical-chain process. These competing reactions cannot be prevented, but reported herein is a method to repair the chain process by running the reaction in the presence of triethylborane and catechol. Under these reaction conditions, a unique repair mechanism leads to an efficient chain reaction, which is demonstrated with a broad range of anomeric O-allyl sugar derivatives including mono-, di-, and tetrasaccharides bearing various functionalities and protecting groups. In good repair: Undesired hydrogen-atom transfers are responsible for the lack of efficiency in thiol-ene coupling reactions involving allyl glycosides. This competing reaction cannot be prevented but can be very efficiently repaired by carrying out the reaction in the presence of triethylborane and catechol.

(Azetidin-1-ylalkyl) lactams as tachykinin antagonists

The present invention provides compounds of formula (I) and the pharmaceutically acceptable salts thereof, wherein R is C3 -C7 cycloalkyl, aryl or C1 -C6 alkyl, said C1 -C6 alkyl, said C1 -C6 alkyl being optionally substituted by fluoro, COOH, --COO(C1 -C4 alkyl), C3 -C7 cycloalkyl, adamantyl, aryl or het1, and said C3 -C7 cycloalkyl being optionally substituted by 1 or 2 substituents each independently selected from C1 -C4 alkyl, C3 -C7 cycloalkyl, C1 -C4 alkoxy, hydroxy, fluoro, fluoro (C1 -C4) alkyl and fluoro (C1 -C4) Alkoxy; R1 is phenyl, naphthyl, thienyl, benzothienyl or indolyl, each optionally substituted by 1 or 2 substituents each independently selected from C1 -C4 alkyl, C1 -C4 alkoxy, halo and trifluormethyl; R2 is --CO2 H, --CONR3 R4, --CONR5 (C3 -C7 cycloalkyl), --NR5 (C2 -C5 alkanoyl), --NR3 R4, --NR5 CONR5 R6, (C3 -C7 cycloalkyl-C1 -C4 alkyl)R5 N--, --NR5 COCF3, --NR5 SO2 CF3, --NR5 (SO2 C1 -C4 alkyl), --NR5 SO2 NR5 R6, --NR5 (SO2 aryl), --N(aryl) (SO2 C1 -C4 alkyl), --OR5, --O(C3 -C7 cycloalkyl), --SO2 NR5 R6, het3 or a group of formulas: (a), (b), (c), (d), (e), (f), (g) or (h); X is C1 -C4 alkylene; X1 is a direct link or C1 -C6 alkylene; X2 is a direct link, CO, SO2, or NR5 CO; and m is 0, 1 or 2; together with intermediates used in the preparation of compositions containing and the use as tachykinin angatonists of such derivatives. STR1

Reactions of Some Cyclopropylethylenes with TCNE. A Remarkable Effect of Spiro-Activation in the Cycloaddition

Previously, mono-, di-, and trisubstituted vinylcyclopropanes 1 have been shown to react with TCNE to give a cyclobutane derivative 2 (type I reaction).However, it was observed that the introduction of a spiro-linked fluorene group to the three-membered ring, as in 5, 7, and 8, resulted in a total change of the reaction pathway to produce a vinylcyclopentane derivative (type II reaction), which was formerly observed to occur only in the reaction of tetrasubstituted ethylene 3.The results may be rationalized in terms of the SET initiation of the reaction, which is supposed to be ascribed to the spiro-activation.The chemical behavior of various substrates (5-9 and 15) as well as their relative reactivities are discussed.

OLIGOMETHYLENATION OF BICYCLOPROPYLIDENE BY DIAZOMETHANE IN THE PRESENCE OF PALLADIUM(II) ACETATE

Oligomethylenation, leading to the inclusion of three or four equivalents of methylene in the molecule, takes place during the reaction of bicyclopropylidene with diazomethane in the presence of palladium(II) acetate.

REARRANGEMENT OF LITHIUM DERIVATIVES OF CYCLOPROPYL-SUBSTITUTED METHYLENECYCLOPROPANES

Cyclopropyllithium compounds, produced by the metallation of 1,1-dicyclopropyl- and 1-methyl-1-cyclopropylmethylenecyclopropanes with the butyllithium-tetramethylethylenediamine complex, undergo thermal rearrangement and give, after treatment of the reaction mixture with water, spirohept-4-enes.A possible rearrangement scheme is proposed and discussed.

PROTON MOBILITY OF HYDROGEN IN SUBSTITUTED METHYLENECYCLOPROPANES AND VINYLCYCLOPROPANES

The kinetic acidities of methylenecyclopropane, 1,1-dicyclopropylmethylenecyclopropane, and 1-methyl-1-cyclopropylmethylenecyclopropane in the KCH2SOCH3-(CH3)2SO system were determined; the rate constants for the isomerization of the last hydrocarbon into 1,1-dicyclopropylethylene and of 1,1,dimethylmethylenecyclopropane into 1-methyl-1-cyclopropylethylene were also determined.The introduction of the vinyl group into the trimethylene ring and also the introduction of an exocyclic double bond lead to a marked increase in the proton mobility of the hydrogen.Electron-donating methyl and cyclopropyl groups at the double bond of methylenecyclopropane reduce its kinetic acidity.

REACTION OF METHYLENE BROMIDE WITH DICYCLOPROPYL KETONE IN THE PRESENCE OF TITANIUM TETRACHLORIDE AND ZINC

1,1-Dicyclopropylethylene and 1,1-dicyclopropylcyclopropane were obtained as a result of the reaction of dicyclopropyl ketone with methylene bromide in the presence of titanium tetrachloride and zinc.