SECONDARY AND TERTIARY ALKYL KETONES FROM CARBOXYLIC ACID CHLORIDES AND LITHIUM PHENYLTHIO(ALKYL)CUPRATE REAGENTS: tert-BUTYL PHENYL KETONE

1976 ◽  
Vol 55 ◽  
pp. 122 ◽  
Inorganics ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 76 ◽  
Author(s):  
Yasunobu Egawa ◽  
Chihiro Fukumoto ◽  
Koichiro Mikami ◽  
Nobuhiro Takeda ◽  
Masafumi Unno

Carboxylic acid chlorides are useful substrates in organic chemistry. Many germanium analogues of carboxylic acid chloride have been synthesized so far. Nevertheless, all of the reported germathioacid chlorides use bidentate nitrogen ligands and contain germanium-nitrogen bonds. Our group synthesized germathioacid chloride, Ge(S)Cl{C6H3-2,6-Tip2}(Im-i-Pr2Me2), using N-heterocyclic carbene (Im-i-Pr2Me2). As a result of density functional theory (DFT) calculation, it was found that electrons are localized on sulfur, and the germanium-sulfur bond is a single bond with a slight double bond property.


Author(s):  
G. I. Podzigun ◽  
N. G. Pashkurov ◽  
V. S. Reznik ◽  
B. E. Ivanov

Synlett ◽  
2020 ◽  
Vol 32 (01) ◽  
pp. 45-50
Author(s):  
Udo Nubbemeyer ◽  
Analuisa Nava ◽  
Lukas Trippe ◽  
Andrea Frank ◽  
Lars Andernach ◽  
...  

AbstractStarting from methyl cycloheptatrienyl-1-carboxylate, 6-acylation was successfully achieved employing glutaryl chloride in the presence of AlCl3 under controlled reaction conditions to furnish keto carboxylic acid product. After protection of this keto carboxylic acid as tert-butyl ester, reagent-controlled enantioselective reductions delivered configuration-defined methyl-6-hydroxylalkyl cycloheptatriene-1-carboxylates with up to 80% ee. Whereas simple NaBH4 reduction of the keto carboxylic acid and subsequent lactonization afforded a methyl-6-tetrahydropyranonyl cycloheptatriene-1-carboxylate. Resolution using chiral HPLC delivered the product enantiomers with up to >99% ee Finally, ECD analyses enabled structure elucidation. The products are used as key intermediates in enantioselective 6,11-methylene-lipoxin B4 syntheses.


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