Synthesis of (E)-α-Hydroxyethyl-α,β-Unsaturated Aldehydes by the Reaction of Tetrahydrofuran and Aromatic Aldehydes

2-Azaallyl anions are valuable intermediates which have versatile applications in functionalization with various electrophiles. Decarboxylation of the imines formed from aromatic aldehydes and α,α-diphenylglycine provides an interesting and efficient way to generate delocalized 2-azaallyl anions, which display high reactivity toward different electrophiles with excellent regioselectivity at the diphenylketimino aryl carbon of the 2-azaallyl anions. The transformation produces various amines in good yields under very mild conditions. This Synpacts article highlights the recent advances on the decarboxylative umpolung synthesis of amines from carbonyl compounds.1 Introduction2 Decarboxylative Umpolung Reactions of Carbonyl Compounds with Different Electrophiles2.1 Reaction with π-Allyl–Pd(II) Species2.2 Reaction with Morita–Baylis–Hillman Adducts2.3 Reaction with Imines2.3.1 Intermolecular Reaction with N-Ts Imines2.3.2 Intramolecular Reaction with Chiral N-tert-Butanesulfinyl Imines2.4 Reaction with Aldehydes and Ketones3 Decarboxylative Umpolung Reaction of α,β-Unsaturated Aldehydes with Aldehydes4 Conclusion

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Synthesis of aromatic aldehydes by organocatalytic [4+2] and [3+3] cycloaddition of α,β-unsaturated aldehydes

Tetrahedron ◽

10.1016/j.tet.2007.01.039 ◽

2007 ◽

Vol 63 (13) ◽

pp. 2840-2850 ◽

Cited By ~ 59

Author(s):

Bor-Cherng Hong ◽

Hsing-Chang Tseng ◽

Shang-Hung Chen

Keyword(s):

Aromatic Aldehydes ◽

Unsaturated Aldehydes

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Synthesis of Aromatic Aldehydes by Organocatalytic [4 + 2] and [3 + 3] Cycloaddition of α,β-Unsaturated Aldehydes.

ChemInform ◽

10.1002/chin.200727069 ◽

2007 ◽

Vol 38 (27) ◽

Author(s):

Bor-Cherng Hong ◽

Hsing-Chang Tseng ◽

Shang-Hung Chen

Keyword(s):

Aromatic Aldehydes ◽

Unsaturated Aldehydes

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A modular olefination reaction between aldehydes and diborylsilylmethide lithium salts

Chemical Communications ◽

10.1039/d1cc01882e ◽

2021 ◽

Author(s):

Elena Fernandez ◽

Oriol Salvado

Keyword(s):

Wittig Reaction ◽

Aromatic Aldehydes ◽

Lithium Salts ◽

Unsaturated Aldehydes ◽

Trisubstituted Alkenes

We describe the preparation of densely functionalised 1,1,-silylborylated trisubstituted alkenes, via boron-Wittig reaction, between LiC(Bpin)2(SiMe3) and aliphatic or aromatic aldehydes. The condensation of diborylsilylmethide lithium salts with α,β-unsaturated aldehydes provides...

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Kinetics of catalytic Meerwein-Ponndorf-Verley reduction of aldehydes and ketones using boron triethoxide

Chemical Papers ◽

10.2478/s11696-009-0098-3 ◽

2010 ◽

Vol 64 (1) ◽

Cited By ~ 5

Author(s):

Burcu Uysal ◽

Birsen Buyuktas

Keyword(s):

Room Temperature ◽

Aromatic Aldehydes ◽

Reduction Reaction ◽

Aliphatic Aldehydes ◽

Unsaturated Aldehydes ◽

Aldehydes And Ketones ◽

Kinetics Of ◽

Membered Transition State ◽

Mpv Reduction ◽

Respective Rate

AbstractCatalytic Meerwein-Ponndorf-Verley (MPV) reduction of various aliphatic, aromatic, and unsaturated aldehydes and ketones to corresponding alcohols (analyzed by GC-MS) in the presence of boron triethoxide (B(OEt)3) were studied. Kinetics of this reduction reaction was also studied and the respective rate constants were determined. It was found that B(OEt)3 catalyzes the reduction of aliphatic aldehydes and ketones to alcohols at room temperature while aromatic aldehydes and ketones were not reduced under the same conditions. In addition, MPV reduction using B(OEt)3 was found to be chemoselective as unsaturated aldehydes and ketones afforded the corresponding alcohols without affecting unsaturated groups. The mechanism proposed involves a six-membered transition state in which both the alcohol and the carbonyl are coordinated to the same boron centre of a boron alkoxide catalyst.

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