Highly Diastereoselective Reformatsky-Type Reaction Promoted by Tin Iodide Ate Complex

Abstract

[reaction: see text] An ate type of tin complex, Li(+)[n-Bu(2)SnI(3)](-)/HMPA, works as a novel type of reagent to accomplish the highly diastereoselective Reformatsky-type reaction by the halogen-metal exchange method.

The Aldol Reaction under High‐Intensity Ultrasound: A Novel Approach to an Old Reaction

“…[26] We have also examined some stereochemical aspects of these reactions in a few preliminary experiments. Our operating conditions did not influence the diastereoselectivity of the AR: although propiophenone reacted with 4-nitrobenzaldehyde, 3-nitrobenzaldehyde and pyridine 3-carboxaldehyde [27] to afford the corresponding aldols in good yields (30 min; 69, 77 and 72%, respectively), the poor diastereoisomeric excess (monitored by GC: OV1, film 0.4 µm) observed previously [28] was hardly improved (10Ϫ13% vs. 7Ϫ8%).…”

Zn(pybox)‐Complex‐Catalyzed Asymmetric Aqueous Mukaiyama‐Aldol Reactions.

“…General: Optical rotations were measured with a Digital Polarimeter at room temperature. 1 H NMR spectra were recorded on 400 and 500 MHz spectrometers in CDCl 3 with Me 4 Si as internal standard. High resolution mass spectra were taken on a mass spectrometer with timeof-flight (TOF) detector.…”

“…(2S,3S)-3-Hydroxy-2-methyl-1,3-diphenyl-propan-1-one (6) 1,2 OH O 6 1 H NMR (200 MHz) δ (syn): 1.19 (d, 3H, J 7.2 Hz), 3.67 (d, 1H, J 1.7 Hz), 4.11 (dq, 1H, J 3.0, 7.3 Hz), 5.23 (brs, 1H), 7.20 -7.65 (m, 8H), 7.85-8.20 (m, 2H). 13 C NMR (50 MHz) δ: 11.1, 47.1, 73.0, 125.9, 127.…”

“…Cl OH O 7e 1 H NMR (200 MHz) δ (syn): 1.17 (d, 3H, J 7.2 Hz), 3.64 (dq, 1H, J 3.2, 7.3 Hz), 3.82 (d, 1H, J 1.9 Hz), 5.20 (t, 1H, J 3.0 Hz), 7.25-7.65 (m, 8H), 7.88-8.10 (m, 2H). 13 C NMR (50 MHz) δ: 11.…”

Special Issue: Recent Advances in Organotin Chemistry

“…Interest in organotins from organic chemistry is increasing: for example, very recently a highly diastereoselective Reformatsky-type reaction has been found to be promoted by an organotin iodide complex [20], whereas cationic distannoxane catalysts have been applied to carbon-carbon bond formation [21]. Tin(IV)chloride chiral pyrogallol derivatives have been employed as new Lewis acid-assisted chiral Bronsted acids for enantioselective polyene cyclization [22] whereas mild and selective methods for hydrolysis of ester employ trimethyltin hydroxide [23].…”