215780-24-8

Basic information

• Product Name: 6-Methyl-3-{[((Z)-2-methyl-but-2-enyl)-diphenyl-silanyl]-methyl}-hept-5-en-2-one
• Synonyms: 6-Methyl-3-{[((Z)-2-methyl-but-2-enyl)-diphenyl-silanyl]-methyl}-hept-5-en-2-one
• CAS NO: 215780-24-8
• Molecular Weight: 390.641
• Mol File: 215780-24-8.mol

Chemical Properties

• CAS DataBase Reference: 6-Methyl-3-{[((Z)-2-methyl-but-2-enyl)-diphenyl-silanyl]-methyl}-hept-5-en-2-one(CAS DataBase Reference)
• NIST Chemistry Reference: 6-Methyl-3-{[((Z)-2-methyl-but-2-enyl)-diphenyl-silanyl]-methyl}-hept-5-en-2-one(215780-24-8)
• EPA Substance Registry System: 6-Methyl-3-{[((Z)-2-methyl-but-2-enyl)-diphenyl-silanyl]-methyl}-hept-5-en-2-one(215780-24-8)

Safety Data

• Hazardous Substances Data: 215780-24-8(Hazardous Substances Data)

Upstream product

• 78-79-5 isoprene 
• 215780-38-4 N-Methyl-N-methoxy-2-methylene-5-methylhex-4-enamide 
• 54109-51-2 ethyl 5-methyl-2-methylenehex-4-enoate 
• 215780-36-2 2-Methylene-5-methylhex-4-enoic acid 
• 870-63-3 prenyl bromide 
• 63812-04-4 (Z)-trichloro(2-methylbut-2-en-1-yl)silane 
• 26732-90-1 3-(3-methyl-but-2-enyl)-pentane-2,4-dione 
• 182412-80-2 7-methyl-3,4-dimethyleneoct-6-en-2-one 
• 215033-01-5 chloro[(2Z)-2-methylbut-2-en-1-yl]diphenylsilane 

Downstream Products

• 215780-26-0 Fluoro-(2-isopropenyl-5-methyl-hex-4-enyl)-diphenyl-silane 
• 58461-27-1 (+/-)-lavandulol 
• 215780-25-9 (2-Isopropenyl-5-methyl-hex-4-enyl)-((Z)-2-methyl-but-2-enyl)-diphenyl-silane 

Relevant articles and documents

Conjugate addition of silyl groups to β-unsubstituted enones, and Si-to-OH conversion: A synthesis of (±)-lavandulol

TMS chloride raises the yield in the conjugate addition of silylcuprates and zincates to β-unsubstituted enones, and Si-to-OH conversion is possible using the 2-methylbut-2-enyl(diphenyl)silyl group in the presence of highly nucleophilic alkenes. Both reactions are used in a synthesis of lavandulol.

A synthesis of (±)-lavandulol using a silyl-to-hydroxy conversion in the presence of 1,1-disubstituted and trisubstituted double bonds

Silylcuprates and silylzincates react with α,β-unsaturated aldehydes, esters, ketones and amides 19 unsubstituted at the β-position in higher yield if trimethylsilyl chloride is present. Applying this method, conjugate addition of the silylcuprate 26 derived from (Z)-chloro(2-methylbut-2-enyl)diphenylsilane 24, itself prepared by an improved route, to 3-methylene-6-methylhept-5-en-2-one 25 gave 3-[(Z)-2-methylbut-2-enyl(diphenyl)silyl]methyl-6-methylhept-5-en-2-one 27. A Wittig reaction gave 3-[(Z)-2-methylbut-2-enyl(diphenyl)silyl]methyl-2,6-dimethylhepta-1,5-diene 28 and silyl-to-hydroxy conversion gave lavandulol 1, even in the presence of the 1,1-disubstituted and trisubstituted double bonds. The hydroxy group of the 3-hydroxysilane, 2,6-dimethyl-3-{[(Z)-2-methylbut-2-enyl]diphenylsilyl}methylhept-5-en-2-ol 30, activated the allylsilane group towards protodesilylation. Chloro(diphenyl)methallylsilane 35 is easier to make than the chloride 24, and should be an alternative allylsilane that can make a lithium and hence a cuprate reagent like 26.