156275-96-6

Basic information

• Product Name: TRIISOPROPYLSILANETHIOL
• Synonyms: TRIISOPROPYLSILANETHIOL;1,1,1-Tris(1-methylethyl)silanethiol;Triisopropylsilylthiol;Triisopropylsilanethiol 97%;Silanethiol,1,1,1-tris(1-methylethyl)-;Triisopropylsilanethiol 95%+;tri(propan-2-yl)-sulfanylsilane
• CAS NO: 156275-96-6
• Molecular Formula: C₉H₂₂SSi
• Molecular Weight: 190.42
• Product Categories: Organometallic Reagents;Organosilicon;Others;Chemical Synthesis;Organometallic Reagents
• Mol File: 156275-96-6.mol
• Article Data: 5

Chemical Properties

• Boiling Point: 70-75 °C2 mm Hg(lit.)
• Flash Point: 171 °F
• Appearance: /
• Density: 0.887 g/mL at 25 °C(lit.)
• Vapor Pressure: 0.277mmHg at 25°C
• Refractive Index: n20/D 1.479(lit.)
• Solubility: Soluble in most organic solvents.
• PKA: 9.86±0.10(Predicted)
• CAS DataBase Reference: TRIISOPROPYLSILANETHIOL(CAS DataBase Reference)
• NIST Chemistry Reference: TRIISOPROPYLSILANETHIOL(156275-96-6)
• EPA Substance Registry System: TRIISOPROPYLSILANETHIOL(156275-96-6)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 26-36
• RIDADR: UN 3334
• WGK Germany: 3
• Hazardous Substances Data: 156275-96-6(Hazardous Substances Data)

Usage

Description

Triisopropylsilanethiol, also known as TIPS-SH, is an organosilicon compound with the chemical formula (C3H7)3SiSH. It is a colorless liquid and serves as a convenient synthetic equivalent of hydrogen sulfide (H2S) in various chemical reactions. Triisopropylsilanethiol is characterized by its reactivity as a nucleophile and its ability to act as a polarity-reversal catalyst in radical reactions.

Uses

1. Used in Organic Synthesis:
Triisopropylsilanethiol is used as a nucleophile in the synthesis of alkanethiols and unsymmetrical dialkyl sulfides. It is prepared in quantitative yield (98%) from the reaction of LiSH (readily obtained by reacting H2S with n-BuLi in THF) with TIPSCl at -78°C.
2. Used in Synthesis of 9-BBN-derived Alkyl and Aryl Boranes:
Triisopropylsilanethiol plays a crucial role in the synthesis of 9-BBN-derived alkyl and aryl boranes, which are important intermediates in organic chemistry.
3. Used in Palladium-catalyzed Cross-coupling Reactions:
In the Pd0-catalyzed cross-coupling of vinyl and aryl halides with KSTIPS, triisopropylsilanethiol is used to afford the corresponding silyl sulfides. These silyl sulfides can be further utilized to prepare thiols or sulfides.
4. Used as Ligand in Ziegler-Natta Polymerization of Ethylene:
Triisopropylsilanethiol is employed as a ligand in the Ziegler-Natta polymerization of ethylene in solution. A medium pressure process for the polymerization of ethylene has been developed in the presence of a catalytic system involving a monocyclopentadienyl titanium species, containing TIPSthiolate as the heteroligand and two activable ligands (2Cl or 2Me), associated with an ionic activator such as triphenylcarbenium tetrakis(pentafluorophenyl)borate.
5. Used in Radical Reactions:
Triisopropylsilanethiol is used as a polarity-reversal catalyst in radical reactions, specifically in the radical reduction of alkyl halides by silanes. According to Roberts, the thiol acts as a polarity-reversal catalyst, promoting the reaction.
Physical properties:
Triisopropylsilanethiol has a boiling point of 70-73 °C (2 mmHg) and a density of 0.887 g/cm3.

InChI:InChI=1/C9H22SSi/c1-7(2)11(10,8(3)4)9(5)6/h7-10H,1-6H3

Upstream product

• 13154-24-0 triisopropylsilyl chloride 
• 6485-79-6 chlorotriisopropylsilane 

Downstream Products

• 540721-69-5 (5R)-5-[(1E)-3-hydroxy-4-phenylbut-1-enyl]-1-{4-[(triisopropylsilyl)thio]butyl}-pyrrolidin-2-one 
• 474658-40-7 3-[1,1-bis(methylethyl)-2-methyl-1-silapropylthio]phenyl acetate 
• 123231-01-6 (4-bromophenylsulfanyl)-triisopropylsilane 
• 156098-16-7 triisopropyl-(4-methoxyphenylsulfanyl)-silane 
• 1849-36-1 para-nitrobenzenethiol 
• 624730-34-3 4-methylphenyl triisopropylsilyl sulfide 
• 179421-15-9 4-cyano-4-{3-[tri-(1-methylethyl)]silylthiophenyl}-3,4,5,6-tetrahydro-2H-pyran 
• 156098-13-4 phenyl triisopropylsilyl sulfide 
• 955024-69-8 triisopropyl(2-(p-tolylethynyl)phenylthio)silane 
• 660391-76-4 Benzoic acid (2R,3R,4R,5R,6R)-5-azido-3,4-dihydroxy-6-triisopropylsilanylsulfanyl-tetrahydro-pyran-2-ylmethyl ester 
• 660391-90-2 C₅₃H₆₁N₃O₁₅SSi 
• 660391-78-6 C₅₆H₆₁N₃O₁₄SSi 
• 360055-64-7 1-(1,2-bis-triisopropylsilanylsulfanyl-vinyl)cyclohexene 

Relevant articles and documents

NOVEL HETEROARYL-TRIAZOLE COMPOUNDS AS PESTICIDES

The present invention relates to novel heteroaryl-triazole compounds of the general formula (I), in which the structural elements X, R1, R2, R3, R4 and R5 have the meaning given in the description, to

The mechanism of polarity-reversal catalysis as involved in the radical-chain reduction of alkyl halides using the silane-thiol couple

The mechanism by which thiols promote the radical-chain reduction of alkyl halides by a variety of simple silanes, such as Et3SiH and Ph3SiH, has been investigated in detail. Kinetic studies of the thiol-catalysed reduction of 1-bromooctane and of 1-chlorooctane by Et3SiH in cyclohexane at 60°C are consistent with a mechanism that involves reversible abstraction of hydrogen by the thiyl radical from the silane, followed by abstraction of halogen from the octyl halide by the resulting triethylsilyl radical and quenching of the derived octyl radical by the thiol to give octane. On the basis of this mechanism, rate constants for abstraction of hydrogen from Et3SiH by the adamantane-1-thiyl radical (kXSH) and for transfer of hydrogen in the reverse direction (KSiH) were determined as 3.2 × 104 M-1 s-1 and 5.2 × 107 M-1 s-1, respectively, at 60°C. The equilibrium constant kXSH/kSiH is thus 6.2 × 10-4 at 60°C and corresponds to ΔrH ≈ ΔrG = +20.4 kJ mol-1 for abstraction of hydrogen from Et3SiH by 1-AdS, implying that the Si-H bond in the silane is stronger by ca. 20 kJ mol-1 than the S-H bond in the alkanethiol. The silanethiol (ButO)3SiSH was found to be a more effective catalyst than 1-AdSH, because kXSH is greater (1.3 × 105 M-1 s-1) while kSiH is very similar (5.1 × 107 M-1 s-1). The value of kXSH/kSiH is now 2.6 × 10-3 at 60°C and thus the S-H bond in this silanethiol is stronger by ca. 4 kJ mol-1 than that in 1-AdSH. The proposed mechanism for alkyl halide reduction is strongly supported by kinetic studies of the thiol-catalysed H/D-exchange between R3SiH/D and XSH/D and the thiol-catalysed racemisation of (S)-ButMePhSiH, radical-chain processes that provide independent confirmation of the values of kXSH derived from octyl bromide reduction. The value of ΔrH determined in this work indicates that abstraction of hydrogen from Et3SiH by an alkanethiyl radical in cyclohexane solvent is ca. 11 kJ mol-1 less endothermic than implied by the difference in the currently-favoured experimental gas-phase dissociation enthalpies for the Et3Si-H and MeS-H bonds.

THIOLS, UNSYMMETRICAL SULFIDES AND THIOACETALS FROM THE NEW REAGENT: TRIISOPROPYLSILANETHIOL

Triisopropylsilanethiol (HSTIPS, 1), easily prepared in 98percent yield from H2S and TIPSCl, is efficiently alkylated in a selective manner with 10 and 20 alkyl halides or tosylates through its potassium thiolate (2c) to provide RSTIPS (3) in excellent yields.Compound 3 provides a convenient source of alkanethiols (4), unsymmetrical dialkyl sulfides (5) and thioacetals (6).