Reduction of acid chlorides and esters
المؤلف:
University of Missouri System
المصدر:
Organic Chemistry ii
الجزء والصفحة:
.................
17-10-2020
4126
Reduction of acid chlorides and esters
Acid (acyl) chlorides can be converted to aldehydes using lithium tri-tert-butoxyaluminium hydride (LiAlH(Ot-Bu)3). The hydride source (LiAlH(Ot-Bu)3) is a weaker reducing agent than lithium aluminum hydride. Because acid chlorides are highly activated they still react with the hydride source; however, the formed aldehyde will react slowly, which allows for its isolation.
General reaction:
Acid chlorides can be converted to aldehydes using lithium tri-tert-butoxyaluminium hydride (LiAlH(Ot-Bu)3). The hydride source (LiAlH(Ot-Bu)3) is a weaker reducing agent than lithium aluminum hydride. Because acid chlorides are highly activated they still react with the hydride source; however, the formed aldehyde will react slowly, which allows for its isolation.
General Reaction:
Esters can be converted to aldehydes using diisobutylaluminium hydride (DIBAH). The reaction is usually carried out at -78 oC to prevent reaction with the aldehyde product.
Esters can be converted to 1o alcohols using LiAlH4, while sodium borohydride (NaBH4
) is not a strong enough reducing agent to perform this reaction.
Mechanism
1) Nucleophilic attack by the hydride
2) Leaving group removal
3) Nucleophilic attack by the hydride anion
4) The alkoxide is protonated
Going from reactant to products simplified
الاكثر قراءة في مواضيع عامة في الكيمياء العضوية
اخر الاخبار
اخبار العتبة العباسية المقدسة
