3975-81-3

Upstream product

• 54396-68-8 3-diazo-2,2,4,4-tetramethylpentane 
• 84543-57-7 2,4,6-tri-(tert-butyl)thiobenzaldehyde 
• 35383-91-6 2,4,6-tri-tert-butylphenyllithium 
• 102737-62-2 O-t-butyl selenoformate 
• 57701-23-2 O-Cholesteryl-selenoformat 
• 109-73-9 N-butylamine 
• 908093-98-1 diazodiphenylmethane 
• 4351-55-7 cholesteryl formate 
• 630-19-3 pivalaldehyde 
• 78-84-2 isobutyraldehyde 
• 81331-45-5 2-diazo-1,1,3,3-tetramethylindane 
• 107-31-3 Methyl formate 
• 19873-22-4 2,2',4,4',6,6'-hexa-tert-butylbenzil 
• 2904-57-6 mesitylenecarbonitrile oxide 

Downstream Products

• 121654-29-3 2,2',4,4',6,6'-hexa-tert-butylstilbene 

Relevant academic research and scientific papers

Photocycloaddition and ortho-hydrogen abstraction reactions of methyl arylglyoxylates: Structure dependent reactivities

In photocycloaddition reactions between methyl arylglyoxylates and certain cyclo-1,3-dienes, the diastereochemical outcome of the photoproducts is shown to depend on the steric demand of the aryl group in the glyoxylate. Exclusive endo-aryloxetanes were p

Cycloaddition and Oxidation Reactions of a Stable Thioaldehyde, (2,4,6-Tri-t-butyl)thiobenzaldehyde

The title thioaldehyde 1 undergoes [4 + 2] cycloaddition with 2,3-dimethyl-1,3-butadiene at 160°C and [3 + 2] cycloadditions with diphenylnitrilimine and mesitonitrile oxide at room temperature. The intermediary cycloadduct with mesitonitrile oxide undergoes cycloreversion to give 2,4,6-tri-t-butylbenzaldehyde and mesityl isothiocyanate as the final products. Oxidation of 1 with m-chloroperbenzoic acid (mCPBA) and dimethyldioxirane (9) gives a mixture of (E)- and (Z)-isomers of the corresponding S-oxides (sulfines), the former and the latter being kinetically and thermodynamically controlled products, respectively. Although both (E)- and (Z)-sulfines are not further oxidized by mCPBA, the (Z)-sulfine is oxidized with 9 to give 7-oxa-8-thia-2,4,6-tri-t-butylbicyclo[4.3.0]nona-2,4,9-triene 8,8-dioxide and 6,8-di-t-butyl-3,4-dihydro-4,4-dimethyl-1H-2-benzothiopyran 2,2-dioxide, both of which are intramolecular cyclization products of an intermediary thioaldehyde dioxide (sulfene).

2-(2,4-Di-tert-butylphenyl)-1,1-bis(trimethylsilyl)silene and 2-(2,4,6-Tri-tert-butylphenyl)-1,1-bis(trimethylslyl)silene - Two new sterically protected but still unstable silaethenes

(2,4-Di-terl-butylphenyl)tris(trimethylsilyl)silylmethanol (1a), prepared by the reaction of tris(trimethylsilyl)silylmagnesium bromide with 2,4-di-tert-butylbenzaldehyde, was deprotonated by treatment with methyllithium in ether at -78°C to give the transient 2-(2,4-di-tert-butylphenyi)-1,1-bis(trimethylsilyljsilene (3a), which dimerizes in a head-to-head fashion with the formation of (E)-/(Z)-3,4-bis(2,4-di-terf-butylphenyl)-1,1,2,2-tetrakis(trimethylsilyl)-l,2- disilacyclobutane (5). Besides 5 an unstable compound 4 was obtained, which was preliminarly assigned as 5,7-di-terf-butyl-l-(2,4-di-fert-butylphenyl)-1,2,3,8a-tetrahydro-2,2,3,3- tetrakis(trime thylsilyl)-1,2-disilanaphthalene (4), the formal [2 + 4] cyclodi-mer of 3a. Compound 4 gradually decomposes to give (E)-/(Z)-5, and is considered to be the kinetically preferred dirner of 3a, which is converted into the thermodynamically stable 5. 2,4,6-Tri-tert-butylbenzaldehyde reacts with tris(trimethylsilyljsilyllithium resulting in the formation of 6,8-ditert-butyl-l,2,3,4-tetrahydro-4,4-dimethyl-2,2-bis(trimethylsilyl)-2- silanaphthalene (6). Compound 6 is the product of the insertion of the Si=C bond into the C-H bond of an o-tertbutyl group of the intermediate 2-(2,4,6-tri-ferf-butylphenyl)l,l-bis{t.rimethylsilyl)silene (3b), which despite extreme steric shielding proved to be still unstable. For compounds (Z)-5 and 6 the results of the X-ray analyses are given.

Synthesis, Structure, and Some Reactions of (2,4,6-Tri-t-butyl)thiobenzaldehyde, the First Stable Aromatic Thioaldehyde

The title compound 1 was synthesized by the reaction of 2,4,6-tri-t-butylphenyllithium with O-ethyl thioformate or that of 2,4,6-tri-t-butylbenzaldehyde hydrazone with disulfur dichloride in the presence of triethylamine. The thioaldehyde 1 is a purple cr

Photocyclization of 2,4,6,2′,4′,6′-hexaalkylbenzils

Three of the title compounds - the hexamethyl-, hexaethyl-, and hexaisopropylbenzils - all photocyclize both in solution and as solids to 5,7-dialkyl-2-(2′,4′,6′-trialkylphenyl)-2-hydroxy-1-indanones. At wavelengths 4. Moreover, AM1-level semiempirical calculations suggest that a simple exothermic hydrogen transfer can convert the 1,4-biradical triplet dienol to the same 1,5-biradical formed by δ-hydrogen abstraction. The 1,5-biradical has two major conformations, one leading to Z product and an internally OH-O=C hydrogen bonded one leading to E product. The AM1 computations suggest that the two conformations are of comparable energy and thus implicate 1,5-biradicals as the major precursors to hydroxyindanone products. Stern-Volmer quenching studies indicate a triplet decay rate of 5 × 106 s-1 for the hexaisopropylbenzil. The known behavior of structurally similar monoketones predicts such a rate for δ-hydrogen abstraction but a much slower rate for γ-hydrogen abstraction. However, relative quantum efficiencies parallel those for benzocyclobutenol formation from 2,4,6-trialkylbenzophenones (iPr and Et ～0.3, Me ～0.03). The hexa-tert-butylbenzil undergoes very low quantum yield formation of 3,3-dimethyl-5,7-di-tert-butyl-1-indanone and 2,4,6-tri-tert-butylbenzaldehyde, presumably by δ-hydrogen abstraction and highly efficient radical cleavage of the resulting 1-aroyl-1-indanol.

Reactions of (2,4,6-Tri-t-butyl)thiobenzaldehyde with Diazo Compounds. Synthesis and Reactions of Sterically Congested Thiiranes

Sterically congested thiiranes having a 2,4,6-tri-t-butylphenyl group were synthesized by the reactions of (2,4,6-tri-t-butyl)thiobenzaldehyde with sterically hindered diazo compounds.Thermal desulfurization of the most congested thiirane, 2,2-di-t-butyl-3-(2,4,6-tri-t-butylphenyl)thiirane (15c), did not proceed even upon using highly reactive reagents, such as hexamethylphosphorous triamide or organolithiums.The photoreaction of 15c did not give the corresponding styrene, but afforded several products containing 2,4,6-tri-t-butylbenzothiophene and Dewar benzenes,2,2-di-t-butyl-3-(3,4,6-tri-t-butylbicyclohexa-2,5-dien-2-yl)thiirane and 2-t-butyl-3,3-dimethyl-1-(1,3,5-tri-t-butylbicyclohexa-2,5-diene-2-yl)-1-butene (24), the latter of which is the first example for a vinyl-substituted Dewar benzene.Compound 24 has a unique reactivity, giving a rearrangement product, 2-t-butyl-3,3-dimethyl-1-(1,3,5-tri-t-butylbicyclohexa-2,5-diene-2-yl)-1-butene on thermolysis.

Synthesis and Unusual Photochemical Reaction of Highly Congested 2,4,6-Tri-t-butylstyrene Episulfides

Title compounds were synthesized by the reaction of 2,4,6-tri-t-butylthiobenzaldehyde with some diazomethanes.The photolysis of the most sterically congested episulfide obtained from t-Bu2CN2 gave an unusual product resulting from 1,2-migration of t-butyl

Photoreaction of a Stable Thioaldehyde 2,4,6-Tri-tert-butylthiobenzaldehyde

The photochemical reaction of the only isolable aromatic thioaldehyde ArCHS (1; Ar=2,4,6-tri-tert-butylphenyl) in alkaline medium yields ArCH2CH2Ar (2), ArCH2SCH2Ar (3), 6,8-di-tert-butyl-3,4-dihydro-4,4-dimethyl-1H-2-benzothiine (4) and ArMe (5).A radica

Reactions of 2,4,6-Tri-t-butylphenyllithium with Deuterated Formate, Thioformate and Selenoformate

O-Cholesteryl chalcogenoformates-d, DC(=X)(OR) (2: X=O; 3: X=S; 4: X=Se; R=3β-cholesteryl), were synthesized and allowed to react with 2,4,6-tri-t-butylphenyllithium. 1,3,5-Tri-t-butylbenzene was a main product in each reaction. The other products were 2,4,6-tri-t-butylbenzaldehyde-d (9) for 2, 2,4,6-tri-t-butylthiobenzaldehyde-d for 3, and 9, 6,8-di-t-butyl-1-deuterio-3,4-dihydro-4,4-dimethyl-1H-2-benzoselenin, bis(2,4,6-tri-t-butyl-α-deuteriobenzyl) diselenide, and bis(2,4,6-tri-t-butyl-α-deuteriobenzyl) triselenide for 4.The mechanisms for these reactions have been discussed.

Reactions of 2,4,6-Tri-t-butylphenyllithium with O-Alkyl Selenoformates: Intermediate Formation of 2,4,6-Tri-t-butylselenobenzaldehyde

2,4,6-Tri-t-butylphenyllithium reacts with O-alkyl selenoformates (1) at three different sites (i.e., the selenoformyl carbon, the selenoformyl hydrogen, and the selenium) to give 1,3,5-tri-t-butylbenzene, 2,4,6-tri-t-butylbenzaldehyde, 6,8-di-t-butyl-3,4-dihydro-4,4-dimethyl-1H-2-benzoselenin (11), bis(2,4,6-tri-t-butylphenylmethyl) di(and tri) selenides, bis(2,4,6-tri-t-butylphenyl) diselenide, and dibutyl diselenide depending on the reaction conditions and the alkyl group in 1.The formation of 11 is explained in terms of the intermediacy of 2,4,6-tri-t-butylselenobenzaldehyde, which is trapped by condensation rection with butylamine leading to N-(2,4,6-tri-t-butylbenzylidene)butylamine.Mechanism for the formation of these products is also discussed.