1679-55-6

Basic information

• Product Name: 2H-Pyran-2-one, tetrahydro-5,5-dimethyl-
• CAS NO: 1679-55-6
• Molecular Formula: C7H12O2
• Molecular Weight: 128.171
• Mol File: 1679-55-6.mol
• Article Data: 12

Chemical Properties

• CAS DataBase Reference: 2H-Pyran-2-one, tetrahydro-5,5-dimethyl-(CAS DataBase Reference)
• NIST Chemistry Reference: 2H-Pyran-2-one, tetrahydro-5,5-dimethyl-(1679-55-6)
• EPA Substance Registry System: 2H-Pyran-2-one, tetrahydro-5,5-dimethyl-(1679-55-6)

Safety Data

• Hazardous Substances Data: 1679-55-6(Hazardous Substances Data)

Upstream product

• 3121-82-2 2,2-dimethylpentane-1,5-diol 
• 681-57-2 2,2-dimethylglutaric acid 
• 2938-48-9 3,3-dimethyl glutaric acid anhydride 

Downstream Products

• 27143-31-3 2,2,7,7-tetramethyloctane-1,8-diol 

Relevant articles and documents

(Cyclopentadienone)iron-Catalyzed Transfer Dehydrogenation of Symmetrical and Unsymmetrical Diols to Lactones

Air-stable iron carbonyl compounds bearing cyclopentadienone ligands with varying substitution were explored as catalysts in dehydrogenative diol lactonization reactions using acetone as both the solvent and hydrogen acceptor. Two catalysts with trimethylsilyl groups in the 2- A nd 5-positions, [2,5-(SiMe3)2-3,4-(CH2)4(δ4-C4C= O)]Fe(CO)3 (1) and [2,5-(SiMe3)2-3,4-(CH2)3(δ4-C4C= O)]Fe(CO)3 (2), were found to be the most active, with 2 being the most selective in the lactonization of diols containing both primary and secondary alcohols. Lactones containing five-, six-, and seven-membered rings were successfully synthesized, and no over-oxidations to carboxylic acids were detected. The lactonization of unsymmetrical diols containing two primary alcohols occurred with catalyst 1, but selectivity was low based on alcohol electronics and modest based on alcohol sterics. Evidence for a transfer dehydrogenation mechanism was found, and insight into the origin of selectivity in the lactonization of 1°/2° diols was obtained. Additionally, spectroscopic evidence for a trimethylamine-ligated iron species formed in solution during the reaction was discovered.

Efficient and Selective Cu/Nitroxyl-Catalyzed Methods for Aerobic Oxidative Lactonization of Diols

Cu/nitroxyl catalysts have been identified that promote highly efficient and selective aerobic oxidative lactonization of diols under mild reaction conditions using ambient air as the oxidant. The chemo- and regioselectivity of the reaction may be tuned by changing the identity of the nitroxyl cocatalyst. A Cu/ABNO catalyst system (ABNO = 9-azabicyclo[3.3.1]nonan-N-oxyl) shows excellent reactivity with symmetrical diols and hindered unsymmetrical diols, whereas a Cu/TEMPO catalyst system (TEMPO = 2,2,6,6-tetramethyl-1-piperidinyl-N-oxyl) displays excellent chemo- and regioselectivity for the oxidation of less hindered unsymmetrical diols. These catalyst systems are compatible with all classes of alcohols (benzylic, allylic, aliphatic), mediate efficient lactonization of 1,4-, 1,5-, and some 1,6-diols, and tolerate diverse functional groups, including alkenes, heterocycles, and other heteroatom-containing groups.

Mild and chemoselective synthesis of lactones from diols using a novel metal-ligand bifunctional catalyst.

[reaction: see text] A novel amino alcohol-based Ir bifunctional complex acts as an efficient catalyst for oxidative lactonization of 1,4- or 1,5-diols with a substrate-to-catalyst molar ratio of 200-1000 in acetone or butanone. The reaction proceeds with broad functional group tolerance to give lactone in high yield at room temperature. The catalyst precursor Cp*IrCl[OCH(2)C(C(6)H(5))(2)NH(2)] is isolated and characterized by a single-crystal X-ray analysis.