64839-19-6

Upstream product

• 20107-09-9 (2S,4S)-4-acetoxy-2-bromo-2,6,6-trimethylcyclohexanone 
• 169219-60-7 Acetic acid (1S,4R)-4-hydroxy-3,5,5-trimethyl-cyclohex-2-enyl ester 
• 199921-92-1 (2R,4S)-4-acetoxy-2-bromo-2,6,6-trimethylcyclohexanone 
• 124743-97-1 4-acetoxy-2,6,6-trimethylcyclohexa-2,4-dienone 
• 64839-18-5 (1R,5R)-3,3,5-trimethyl-4-oxocyclohexyl acetate 
• 20548-02-1 (4R,6R)-4-hydroxy-2,2,6-trimethylcyclohexan-1-one 
• 1125-21-9 2,6,6-trimethyl-2-cyclohexene-1,4-dione 
• 141037-63-0 (+/-)-trans-2,6,6-trimethyl-2-cyclohexen-1,4-diol 

Downstream Products

• 64809-50-3 (4S)-4-hydroxy-2,6,6-trimethyl-cyclohex-2-en-one 
• 64809-51-4 4(S)-2,6,6-trimethyl-4-[(trimethylsilyl)oxy]-cyclohex-2-en-1-one 

Relevant academic research and scientific papers

New amidophosphine-phosphinites (tLANOPs) as chiral ligands for asymmetric hydrogenation reactions

The new amidophosphine-phosphinite (AMPP) ligands 4a-g (called tLANOP ligands) derived from the chiral hydroxy amide (R)- or (S)-2-hydroxy-3,3,N- trimethylbutyramide have been prepared in 48-83% yield. The crystal structures of the square planar complexes

Total synthesis of C31-methyl ketone apocarotenoids 3. On the structure of hopkinsiaxanthin: First total synthesis of (all-E)-(3S)- and (9Z)-(3S)-7′-apohopkinsiaxanthin

Optically active (all-E)-(3S)-7′-apohopkinsiaxanthin, previously known as F1, and (9Z)-(3S)-7′-apohopkinsiaxanthin have been prepared by total synthesis for the first time in ca. 1% combined overall yield, including two unidentified geometrical isomers, in sixteen linear steps from (4R,6R)-actinol, (2E)-3-methyl-2-penten-4-yn-1-ol, (7-formyl-2-methyl-2,4,6-octatrienyl)triphenylphosphonium bromide, (3-formyl-2-butenyl)triphenylphosphonium bromide and methyllithium, by use of a C15+C10+C5+C1 approach. By an alternative route from (2Z)-5-[((4S)-4-hydroxy-2,6,6-trimethyl-3-oxo-1-cyclohexenyl)-3-methyl-2-penten- 4-ynyl]triphenylphosphonium bromide, (7-formyl-2-methyl-2,4,6-octatrienyl)triphenylphosphonium bromide and (2E)-3-methyl-4-oxo-2-pentenal, the same target compounds were obtained in a combined overall yield of >61%, including four unidentified geometrical isomers, over two steps, by use of a C15+C16 approach. A hypothetical structure for hopkinsiaxanthin is discussed, based on present and previously reported spectroscopic and chemical data for (all-E)-(3S)- and (9Z)-(3S)-7′-apohopkinsiaxanthin and on data previously reported for hopkinsiaxanthin itself. Acta Chemica Scandinavica 1997.

Lipase-catalyzed asymmetric synthesis of (R)- and (S)-4-tert-butyldimethylsilyloxy-2,6,6-trimethyl-2-cyclohexenone and their dihydro derivatives

Racemic 4-hydroxy-2,6,6-trimethyl-2-cyclohexenone, trans- and cis-2,6,6-trimethyl-2-cyclohexene-1,4-diols were prepared by reduction of 4-oxoisophorone with sodium borohydride-cerium chloride. Lipase (PS-30)-catalyzed kinetic resolution of (±)-cis-2,6,6-trimethyl-2-cyclohexene-1,4-diol with vinyl acetate led to (1R, 4S)-4-acetoxy-2,6,6-trimethyl-2-cyclohexen-1-ol (81%ee) and (1S,4R)-1-acetoxy-2,6,6-trimethyl-2-cyclohexene-4-ol (92%ee). Hydrolysis of the former monoacetate and recrystallization of the resulting material afforded enantiomerically pure (1R, 4S)-2,6,6-trimethyl-2-cyclohexene-1,4-diol. On the other hand, recrystallization of (1S,4R) monoacetate itself provided an optically pure sample, which was then hydrolyzed to give (1S, 4R)-2,6,6-trimethylcyclohexene-1,4-diol. Transformation of both diols into (S)- and (R)-4-tert-butyldimethylsilyloxy-2,6,6-trimethyl-2-cyclohexenone was conducted in two steps including silylation and oxidation. Catalytic hydrogenation of these (S)- and (R)-silyloxy enones over Raney nickel afforded the corresponding dihydro derivatives.

Polyene compounds

15,15'-Didehydro-astaxanthin and ester derivatives thereof useful as coloring agents and intermediates for astaxanthin and a method for preparing astaxanthin from keto α-isophorone and intermediates therein.