2.2.4- Trimethyl-2,4-dihydro

AI3-33978 Cyclohexanone, 3,3,5-trimethyl- Dihydro-isophorone Dihydroisophorone EINECS 212-855-9 3,3,5-... 

CAS 498-81-7 EINECS/ELINCS 207-871-8 Synonyms Cyclohexanemethanol, a,a,4-trimethyl- Dihydro-a-terpinol a,a,4-Trimethylcyclohexanemethanol... 

Trimethyl [dihydro.aaphthyl]-ammoniuin hydnj] 121518. cis-2-Methylamlmo-cyclohezaaol-(l)... 

Alkylated diphenyl amines (11) and derivatives of both dihydro quiaoline (12) and polymerized 2,2,4-trimethyl-l,2-dihydroquiQoline [26780-96-1] (13) develop less color than the -phenylenediamiaes and are classified as semistaining antioxidants. Derivatives of dihydro quiaoline are used for the stabilization of animal feed and spices. 

Naphtho[2,1 -6]furan, 1,5,8-trimethyl- H NMR, 4, 562 (75JCS(P1)478) Naphtho[l,2-6]phosphorin, 2-t-butyl-5,6-dihydro-4-... 

Thiazole, 2,4,5-trimethyl-thermodynamic data, 6, 245 (66CR(C)(263)1333) Thiazole, 2,2,4-trimethyl-4,5-dihydro- H NMR, 5, 17 (64JCP613)... 

Pterin, 6,7,7-trimethyl-7,8-dihydro-bacteriostatic activity, 3, 325 Pterin, 5,6,7-trimethyl-5,6,7,8-tetrahydro-dihydrochloride monohydrate X-ray analysis, 3, 281 Pterin-6-carbaldehyde, JV -acetyl-synthesis, 3, 312... 

Pyran-4-one, 2,2,5-trimethyl-2,3-dihydro-photodimerization, 3, 720 4H-Pyran-4-one, 2,3-dihydro-2,3,5-trimethyl-6-( 1 -methyl-2-oxobutyl)-synthesis, 3, 844 Pyranones alkylation, 2, 56 aromaticity, 3, 632, 633 C NMR, 3, 587, 635 H NMR, 3, 580 cardiac glycosides, 3, 883 chromone synthesis from, 3, 830 colour couplers... 

Quinoline, 2,2,4-trimethyl-1,2-dihydro-antioxidant in polymers, 1, 395 Doebner-von Miller synthesis, 2, 468 Quinoline, trimethylstannyl-reactions, 2, 364 Quinoline, 4-vinyl-polymers, 1, 286... 

Xanthopterin, 7,7-dimethyl-7,8-dihydro-synthesis, 3, 315 Xanthopterin, 7-methyl-synthesis, 3, 303 Xanthopterin, 7-phenacyl-structure, 3, 276 Xanthopterin, 3,5,7-trimethyl-Claisen condensation, 3, 303 Xanthopterin-7-carboxylic acid reactions... 

Boron-nitrogen heterocycles [4,5-diethyl-2,2,3-trimethyl-l-(<9-tnfluoro-methyl)phenyl-2,5-dihydro-l(-)-],2,5-azasilaboroles and -azastannaboroles] are formed in good yields The products demonstrate atropoisomensm due to the hmdered rotation about the N-aryl bond [113] (equation 88)... 

Similar cycloaddition reactions were observed with methyl vinyl sulfone (48) and )3-nitrostyrene (48,51). Methyl vinyl ketone, on the other hand, is reported to give dihydropyrans as the initial products (50,52,53). Thus (16) on reaction with methyl vinyl ketone at room temperature for 12 hr gave a 60% yield of 2-dimethylamino-3,3,6-trimethyl-3,4-dihydro-2H-pyran (59). 

Interesting results were also obtained on treatment of 2-amino-4,6,6-trimethyl-dihydropyrimidine 50 and 2,4,6,6-tetramethyldihydropyrimidine 51 with CD3OD in the absence of a base (91TL2057). It was shown that, under these conditions, the 4-methyl protons of 50, the 2,4-dimethyl protons of 51, and H(5) in 50 and 51 undergo H-D exchange. The suggested mechanism involves annular (1,4-dihydro 4,5-dihydro) as well as substituent tautomeric equilibria, as shown in Scheme 20 for H-D exchange in 50. 

Reaction of 10-bromo-iV,l,3-trimethyl-7-oxo-2,3-dihydro-7//-pyrido [ 1,2,3-i/e]quinoxaline-6-carboxamide with 2,6-dimethyl-4-(tributylstannyl)-pyridine in the presence of (Ph3P)2Pd(II)Cl in boiling toluene gave 10-(2,6-dimethyl-4-pyridyl) derivative (OOMIPIO). 

Reaction of ethyl 7-bromo-8-fluoro-l-(2-bromo-l-methylethyl)-4-oxo-l,4-dihydroquinoline-3-carboxylate with MeNH2 yielded 10-bromo-A, 1, 3-trimethyl-7-oxo-2,3-dihydro-7//-pyrido[l,2,3-<7e]quinoxaline-3-carboxamide (OOMIPIO). 

Chemical Name ( )-10,11 -dihydro-N,N,/3-trimethyl-5H-dibenzo[a,d] cycloheptene-5-propan-amine... 

Chemical Name 3,7-Dihydro-8-[(2-hydroxyethyl)methylamino]-1,3,7-trimethyl-l H-purine-2,6-dione... 

Pyrolysis of dimethyl 4-methoxy-2,5,7-trimethyl-4,5-dihydro-l//-azepine-3,6-dicarboxylate (6a), or the corresponding 4-succinimido derivative 6b, at 160-180°C in a sublimation tube containing glass beads furnishes the 4//-azepine 7.121... 

With cyanide ion in aqueous ethanol azepinedicarboxylate 3 forms the corresponding racemic 4,5-dihydro-l//-azepine-4-carbonitrile (85%),121,241 whereas with dimethyl 2,5,7-trimethyl-4//-azepinc-3,6-dicarboxylate (6) diastereospecific addition occurs to give racemic lrans-5-me thy 1-4.5-di hydro-1-//-azepine-4-carbonitrile 7 together with a small amount of the trans 4S-methoxy-5 / -methyl compound 8.121... 

Farnesyl, 10-bromo-10,l 1-dihydro-l 1-hydroxy-, acetate [2,6-Dodecadiene-1,11-diol, 10-bromo-3,7,11-trimethyl-, 1-acetate, ( , )-], 113 Ferrocene, 28... 

Cyclische N-Acyl-hydrazone mit einer cnr/o-Hydrazinocarbonyl-Gruppe ergeben ahnlich den entsprechenden Carbonsaure-hydraziden keine einheitlichen Reduktions-produkte. Im Gegensatz zu den acyclischen Acyl-hydrazonen werden hauptsachlich cyclische Hydrazone gebildet. 5-Oxo-3,4,4-trimethyl-l-phenyl-4,5-dihydro-pyrazol er-gibt z. B. 50% d.Th. 3,4,4-Trimethyl-l-phenyl-4,5-dihydro-pyrazol und 20% d.Th. 5-Hydroxy-3,4,4-trimethyl-1 -phenyl-4,5-dihydro-pyrazoV ... 

Zu einer Losung von 4,93 g (0,13 Mol) Lithiumalanat in 100 ml abs. Diathylather wird unterRiihren und un-ter Stickstoff vorsichtig eine Losung von 10 g(0,05 Mol) 3,5,5-Trimethyl-1-acetyl-4,5-dihydro-pyrazol in 20 ml abs. Diathylather gegeben. Man kocht 1 Stde. unter RiickfluB, kiihlt ab, versetzt mit Wasser, saugt ab, wascht mit Diathylather, trocknet das Filtrat mit Kaliumcarbonat und engt ein. Der Riickstand wird i. Vak. destilliert Aus-beute 5,2 g (60°/, d.Th.) Kp2li 63-64°. 

Trimethyl-2-alkyl-5,6-dihydro-4H-l,3-oxazin In einemmitGummi-Kappe und magneti-schem Ruhrwcrk versehenen Riihrkolben werden unter Stickstoff 100 ml abs. THF und 14,1 g (0.1 Mol)... 

Es kann ferner von Phenyl-acetonitril, Cyanessigsaure-athylester und Acrylsaure-nitril ausgegangen werden. lm letzteren Fall wird die Homologisierung durch Michael-Addition eincr C—H-aciden Verbindung an das erhal-tene 4,4,6-Trimethyl-2-vinyl-5,6-dihydro-4H-l,3-oxazin durchgefiihrt1. 

Dagegen erhalt man aus l,2,6-Trimethyl-3,5-diathoxycarbonyl-pyridinium-perchlorat in Acetonitril und Tetraathylammoniumperchlorat als Leitsalz ein Gemisch aus (—1,1 V) 4,4 - und 2,4 -Dihydro-Dimeren4. 

Hydroxy-propyl )-4-phenyl- 263 5 -H ydroxy-3,4,4-trimethyl-1-phenvl -4,5 -dihydro-262... 

Oxo-3,4,4-trimethyl-l -phenyl-4,5-dihydro- 262 3-Phenyl-l-propanoyl-4,5-dihydro- 262 1 -Propyl-3-phenyl-4.5 -dihydro- 262... 

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