One-pot Pd-catalyzed hydrostannation/Stille reaction with acid chlorides as the electrophiles

Lee, Kyoungsoo; Gallagher, William P.; Toskey, Elli A.; Chong, Wenzheng; Maleczka, Robert E.

doi:10.1016/j.jorganchem.2005.11.041

Cited by 16 publications

(5 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Of course, organotin reagents carry the baggage of being relatively toxic, expensive, unstable, etc . Thus, mindful of prior reactions made catalytic in tin through the use of polymethylhydrosiloxane (PMHS) as the stoichiometric reductant and our recent report of a one-pot Pd-mediated hydrostannation/Stille coupling of acid chlorides, we contemplated a tin-catalyzed version of Guibé's method for reducing acid chlorides to aldehydes.…”

mentioning

confidence: 99%

Pd(0)-Catalyzed PMHS Reductions of Aromatic Acid Chlorides to Aldehydes

Lee

Maleczka

2006

Org. Lett.

Self Cite

View full text Add to dashboard Cite

show abstract

mentioning

confidence: 99%

Pd(0)-Catalyzed PMHS Reductions of Aromatic Acid Chlorides to Aldehydes

Lee

Maleczka

2006

Org. Lett.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The mechanism involves the oxidative addition of acyl chlorides to palladium, the transmetalation of the organic group from organometallic reagent to an acyl palladium species, and subsequent reductive elimination, giving the aromatic ketone. Organoboron [4][5][6][7][8][9][10][11][12][13], organotin [14,15] and organozinc [1,2] reagents have been used as organometallic reagents for the synthesis of ketones. Although these reagents are well-documented with regards to their use in transmetalation, only one equivalent of the organic group can be used for the cross-coupling reaction.…”

Section: Introductionmentioning

confidence: 99%

Coupling of acyl chlorides with triarylbismuths catalyzed by palladium bipyridyl complex anchored on nanosized MCM-41: A recyclable and atom-efficient catalytic process for the synthesis of diaryl and alkyl aryl ketones

Chen

Tang

et al. 2009

Journal of Molecular Catalysis A: Chemical

View full text Add to dashboard Cite

“…13 When silyl triflate 1a was irradiated in the microwave oven, complete consumption of the starting material was observed after 15 minutes, and The major drawback of this protocol is the formation of regioisomeric products, which, in some cases (highly nonpolar compounds), cannot be separated by chromatography. The stannylated toluenes 2d and 2d¢ are examples of such an inseparable mixture.…”

mentioning

confidence: 99%

“…Therefore, we next tried to combine the aryl stannane synthesis and the subsequent cross coupling reaction into a one-pot protocol (Scheme 2). 13 When silyl triflate 1a was irradiated in the microwave oven, complete consumption of the starting material was observed after 15 minutes, and…”

mentioning

confidence: 99%

Synthesis of Aryl Stannanes from Silyl Triflates via Aryne Intermediates

Lakshmi¹,

Wefelscheid²,

Kazmaier³

2011

Synlett

View full text Add to dashboard Cite

Aryl stannanes are easily accessible from o-silylated aryl triflates in the presence of KF and Bu 3 SnH. The corresponding arynes are formed in situ, and undergo clean hydrostannation to give a mixture of the regioisomeric aryl stannanes. The whole reaction sequence can also be carried out as a one-pot reaction under microwave irradiation.Vinyl stannanes are interesting building blocks in organic synthesis, 1 and are easily available, for example, by hydrostannations of alkynes. In general, these hydrometallations can be carried out under radical or transition-metalcatalyzed conditions. 2 In principle, aryl stannanes should be accessible by the same protocol using arynes. Based on their high reactivity, the tin hydride addition should be a relatively fast process. Surprisingly, to the best of our knowledge, such a direct synthesis of aryl stannanes via hydrostannation of arynes is not yet been described in the literature. In general, aryl stannanes are obtained from aryl halides via halogen-metal exchange (with Mg, 3 Li 4 or Zn 5 ) and subsequent transmetallation with R 3 SnCl. Alternatively, aryl stannanes can be obtained by Pd-catalyzed coupling of aryl halides with (R 3 Sn) 2 6 or via radicalnucleophilic substitution of triorganostannyl anions and aryl chlorides, aryl phosphates or aryl ammonium salts. 7 Furthermore, Pd-catalyzed distannylations of arynes with (R 3 Sn) 2 have been described. 8 Based on our interest in Mo-catalyzed hydrostannations of alkynes, 9 we were interested to see if such a hydrometallation might also work with arynes. Arynes are easily accessible from o-silylated aryl triflates, 10 which were synthesized according to a known procedure from the corresponding o-bromophenols via O-silylation and a sequence of lithiation/silyl-migration/triflation. 11 We began our investigations with the simple silyl triflate 1a, which does not give regioisomers in the hydrostannation step. In general, arynes are prepared in the presence of fluoride, preferentially under the influence of crown ethers. Therefore, we used these conditions in our first experiments (Table 1). With our hydrostannation catalyst Mo(CO) 3 (CNt-Bu) 3 (MoBl 3 ), a very clean reaction was observed, giving rise to phenylstannane 2a in excellent yield. Although hydrostannations of alkynes in general require reaction temperatures of around 50°C, here the reaction was complete after two hours at room temperature, probably because of the high reactivity of the aryne.We also investigated the influence of other fluoride sources (entries 2-4). Comparable results were obtained with CsF in MeCN, but the use of tetrabutylammonium fluoride (TBAF) and KF in the presence of tetrabutylammonium bromide (TBAB) as phase-transfer catalyst gave significantly lower yields and required longer reaction times. This clearly indicates that aryne formation is the rate determining step. Because the very fast and clean reaction at room temperature was quite surprising, a control experiment was conducted without the Mo catalyst to establish its role (entry 5...

show abstract

One-pot Pd-catalyzed hydrostannation/Stille reaction with acid chlorides as the electrophiles

Cited by 16 publications

References 21 publications

Pd(0)-Catalyzed PMHS Reductions of Aromatic Acid Chlorides to Aldehydes

Pd(0)-Catalyzed PMHS Reductions of Aromatic Acid Chlorides to Aldehydes

Coupling of acyl chlorides with triarylbismuths catalyzed by palladium bipyridyl complex anchored on nanosized MCM-41: A recyclable and atom-efficient catalytic process for the synthesis of diaryl and alkyl aryl ketones

Synthesis of Aryl Stannanes from Silyl Triflates via Aryne Intermediates

Contact Info

Product

Resources

About