199847-86-4

Upstream product

• 266329-24-2 3-bromo-2,2-dimethyl-1-(dimethylphenylsilyl)propan-1-one 
• 69824-23-3 2-(2-methylpropyl)-1,3-dithiane 
• 266329-37-7 2,2-dimethyl-1-(dimethylphenylsilyl)-3-(tetrahydropyran-2-yloxy)propan-1-one 
• 266329-36-6 2,2-dimethyl-1-(dimethylphenylsilyl)-3-(tetrahydropyran-2-yloxy)propan-1-ol 

Downstream Products

• 199847-74-0 3-[(Z)-1-(Dimethyl-phenyl-silanyl)-3-methyl-but-1-enylsulfanyl]-propionic acid ethyl ester 
• 199847-75-1 3-[(Z)-1-(Dimethyl-phenyl-silanyl)-3-methyl-but-1-enylsulfanyl]-propionic acid methyl ester 
• 199847-85-3 (Z)-1-[dimethyl(phenyl)silyl]-3-methylbut-1-enethiol 

Relevant academic research and scientific papers

Can relief of ring-strain in a cyclopropylmethyllithium drive the Brook rearrangement?

α-Cyclopropyl-α-trialkylsilyl alkoxides were formed either by addition of cyclopropyllithiums to acylsilanes or by addition of organolithiums to a cyclopropylformylsilane. [1,2]-Brook rearrangement led to α-silyloxy organolithiums which on warming underwent cyclopropane ring opening and [1,5]-retro-Brook rearrangement to yield γ-silyl ketones. Despite the favourability of the cyclopropane ring opening, the Brook rearrangement still required the presence of an anion stabilising group to proceed. β-Silylketones were similarly formed by Brook-retro-Brook rearrangement on warming acylsilanes with a vinyllithium.

On the radical Brook rearrangement. Reactivity of α-silyl alcohols, α- silyl alcohol nitrite esters, and β-haloacylsilanes under radical-forming conditions

Two alkoxyl radical generation methods, lead tetraacetate treatment of alcohols and photolysis of nitrites, were applied to α-silyl alcohols 21 and to the corresponding nitrites 25 with a view to forming α-silyl alkoxyl radicals 23 and studying their possible radical Brook rearrangement to α- silyloxy carbon radicals 24. LTA treatment of 21 led to their quick and efficient conversion into mixed acetyl-silyl acetals 33 under very mild conditions. Photolysis of α-alkylmonosubstituted α-silyl nitrites 25 to the corresponding aldehydes is considered to proceed through α-silyl alkoxyl radical intermediates 23. A concerted process is, however, proposed for the case of the benzyl nitrites analogues. On the basis of these results, it is postulated that resonance stabilization can have a major influence on the evolution of α-silyl alkoxyl radicals: should this stabilization be possible, they quickly evolve by α-silyl fragmentation; otherwise, they tend to undergo radical Brook rearrangement. It was also found that the radical Brook rearrangement of α-silyl cyclopropyloxyl radicals generated from β- bromoacylsilanes under standard tin-radical conditions is too slow to compete with β-fragmentation.