2632-78-2Relevant academic research and scientific papers
Silanediol-based inhibitor of thermolysin
Kim, Jaeseung,Glekas, Athanasios,Sieburth, Scott McN
, p. 3625 - 3627 (2007/10/03)
The first silanediol inhibitor of thermolysin is reported, prepared by analogy with the Grobelny/Bartlett phosphinate inhibitor. A Cbz group on nitrogen proved to be unstable to the triflic acid mediated silanediol deprotection and was replaced with a dihydrocinnamoyl group. The silanediol was prepared in high purity by hydrolysis of a difluorosilane intermediate and proved to be an effective inhibitor, differing from the phosphinate by a factor of 4 (Ki=41 nM).
Electronic effects and the stereochemistries in rearrangement-displacement reactions of triaryl(halomethyl)silanes with fluoride and with alkoxide ions
Allen, John M.,Aprahamian, Steve L.,Sans, Esther A.,Shechter, Harold
, p. 3561 - 3574 (2007/10/03)
Tetrabutylammonium fluoride (TBAF) reacts with (halomethyl)diphenyl(para-substituted-phenyl)silanes (13, X = Cl), 14 (X = Br), and 15 (X = I) in ether solvents to give fluorodiphenyl(parasubstituted-phenylmethyl)silanes (17a) and fluorophenyl(phenylmethyl)(para-substituted-phenyl)silanes (20a) by attack on silicon and migrations of the phenyl or the para-substituted-phenyl groups to C-1 with displacement of chloride ion. Sodium methoxide in dioxane effects rearrangement displacements of 14 (X = Br) to yield methoxydiphenyl(para-substituted-phenylmethyl)silanes (17b) and methoxyphenyl(phenylmethyl)(para-substituted-phenyl)silanes (20b). The migratory aptitudes of the varied phenyl groups in rearrangement-displacements of 13 with F- at 25°C are p-CF3-Ph, 2.72 > p-Cl-Ph, 1.67 > Ph, 1.00 > p-CH3-Ph, 0.91 > p-CH3O-Ph, 0.58 > p-(CH3)2N-Ph, 0.55. For reactions of 14 with sodium methoxide in dioxane, the migratory aptitudes at 23°C are p-CF3-Ph, 2.53 > p-Cl-Ph, 1.64 > Ph, 1.00 > p-CH3O-Ph, 0.84 > p-CH5-Ph, 0.79 > p-(CH3)2N-Ph, 0.68. The migratory aptitudes in the above rearrangement-displacements are increased by electron withdrawing substituents, and logarithms of the migratory aptitudes give satisfactory linear correlations with σ and/or σ-zero values of the phenyl substituents. Hammett correlations however of the migratory aptitudes from reactions of F- with 13 (X = Cl) at 0 and -20°C, 14 (X = Br) at 23, 0, and -20°C, and 15 (X = I) at 23°C are not linear. (+)-(Bromomethyl)methyl-1 naphthylphenylsilane (23, [α]D23 +8.29°, cyclohexane) reacts with CsF and with TBAF in THF to give benzylfluoromethyl-1-naphthylsilane (51, [α]D25 = 0.00°, cyclohexane) and fluoromethyl-(1 naphthylmethyl)phenylsilane (52, impure) in 10.4:1 ratio along with unchanged 23 ([α]D23 8.29°, cyclohexane). Sodium methoxide and (+)-23 in dioxane at 25°C and at 0°C yield (+)benzylmethoxymethyl-1-naphthylsilane (64) and (+)-methoxymethyl(1-naphthylmethyl)phenylsilane (65) in ～9:1 ratio. The conversions of (+)-23 to (+)-64 occur with 93% inversion about silicon. Reaction of (+)-23 with sodium methoxide at 25°C to give (+)-65 also occurs with inversion. Further, sodium ethoxide and sodium 2-propoxide react with (+)-23 at 20-25°C by rearrangement displacements on silicon with phenyl migrations to yield (+)-benzylethoxymethyl-1-naphthylsilane (69) and (+)-benzylmethyl-1-naphthyl-2-propoxysilane (70), respectively, each with 95% inversion about silicon. The mechanisms of rearrangement-displacements of 13-15 and (+)-23 by fluoride and by alkoxide ions are discussed.
Synthesis and Properties of (Hydroxymethyl)diorganylsilanes
Tacke, Reinhold,Lange, Hartwig,Bentlage, Anke
, p. 3673 - 3677 (2007/10/02)
The synthesis of the (hydroxymethyl)diorganylsilanes R1R2Si(H)CH2OH (4a: R1 = R2 = CH3, 2-silaisobutanol; 4b: R1 = CH3, R2 = C6H5; 4c: R1 = R2 = C6H5) is achieved by the reaction of R1R2Si(Cl)CH2Cl (2a - c) with AcOH/NEt3 to R1R2Si(OAc)CH2OAc (3a - c), fo
SILAETHENE II. DARSTELLUNG UND CHARAKTERISIERUNG VON 1,3-DISILACYCLOBUTANEN
Auner, N.,Grobe, J.
, p. 151 - 178 (2007/10/02)
1,3-Disilacyclobutanes of the types R1R2SiSiR1R2 are prepared (a) by ring synthesis from chloromethylchlorosilanes R1R2Si(CH2Cl)Cl, (b) by thermolysis of monosilacyclobutanes , and (c) by substitution of chlorine with alkyl groups in SiCl-containing 1,3-disilacyclobutanes, obtained by procedures (a) or (b).The compounds have been characterized by analytical and spectroscopic investigations.The synthetic methods are critically compared.
