1- and 2-(trialkylsilyl)ethanols: New silyl reagents from tin, lithium, and boron chemistry

Journal Article · Fri Aug 18 00:00:00 EDT 1989 · Journal of Organic Chemistry; (USA)

DOI:https://doi.org/10.1021/jo00278a014· OSTI ID:6971647

Soderquist, J A; Rivera, I; Negron, A ^[1]

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1. Univ. of Puerto Rick, Rio Piedras (Puerto Rico)

Efficient preparations of isomerically pure 1- and 2-(trialkylsilyl)ethanols from vinylsilanes with borane reagents are described. In the former case, the borane reduction of the appropriate acetylsilane (12) gave good yields (82-94%) of the desired 1-R{sub 3}Si products (13, R = Me, Et, i-Pr). The reaction of ({alpha}-methoxyvinyl)lithium (10) (from Sn/Li exchange) with the appropriate chlorosilanes provided the corresponding ({alpha}-methoxyvinyl)silanes (11) (89-94%). Hydrolysis of 11 afforded acylsilanes (12) in excellent yield (93%). Hydroboration of the vinylsilanes (1) with 9-borabicyclo(3.3.1)nonane (9-BBN) gave ({beta}-borylethyl)silanes (2), which were oxidized to provide isomerically pure 2-silylethanols (3). The formation of Normant's reagent (4, vinylmagnesium bromide in THF) and Seyferth's reagent (7, unsolvated vinyllithium) were examined in some detail, and several new minor processes were identified. Unlike less hindered chlorosilanes, the triisopropylsilyl compound fails to react cleanly with 4, but is smoothly converted to 1c (79%) with 7. It was demonstrated that 11c (R = i-Pr) afforded 3c (89%) via a one-pot hydroboration/elimination/hydroboration/oxidation sequence. Complete, assigned {sup 13}C NMR data for these silanes are presented and compared to their trimethylsilyl counterparts.

• OSTI ID: 6971647
• Journal Information: Journal of Organic Chemistry; (USA), Journal Name: Journal of Organic Chemistry; (USA) Vol. 54:17; ISSN 0022-3263; ISSN JOCEA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALCOHOLS
ALKALI METALS
BORON COMPOUNDS
DATA
DATA ANALYSIS
ELEMENTS
ETHANOL
EXPERIMENTAL DATA
HYDRIDES
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
LITHIUM
MEASURING INSTRUMENTS
MEASURING METHODS
METALS
NUMERICAL DATA
ORGANIC BORON COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
SILANES
SILICON COMPOUNDS
SYNTHESIS
TIN