Amines crotyl

The imines generated in situ from 2-pyridinecarboxaldehyde (or 2-quinolinecarboxaldehyde) and arylamines undergo indium-mediated Barbier allylation in aqueous media to provide homoallylic amines. Crotyl and cinnamyl bromides lead to diastereoselective allylation with diastereomeric ratios up to 98 2 (Equation (60)).260... 

Pd(Ph3P)4, RS02Na, CH2CI2 or THF/MeOH, 70-99% yield. These conditions were shown to be superior to the use of sodium 2-ethylhexanoate. Methallyl, allyl, crotyl, and cinnamyl ethers, the Alloc group, and allyl-amines are all efficiently cleaved by this method. ... 

Reaction of 2-[A -(rra -crotyl)-A -benzylamino]-3-formyl-4/f-pyrido[l,2-n]pyrimidin-4-one (269) with chiral primary amines 270 and 271 gave mixtures of diastereoisomers of tetracyclic compounds 273 and tricyclic 275 (96T131]]). The chiral centers in 272 and 274 did not provide any stereocontrol for the formation of diastereomers 273 and 275, respectively. 

Another way to enhance 1 1 addition of amines to butadiene consists of the use of catalytic amounts of protic acids, which apparently give rise to 7r-crotyl groups (234). 

Syntheses of primary ally lie amines have been reviewed183. The regiochemistry of the reaction of iron carbonyl complexes with nucleophiles such as morpholine has been investigated. The (r 3-crolyl) Fe+(CO)4 BF4- complexes 172 (R1 = H R2 = Me or R1 = Me R2 = H) undergo preferential attack at the less substituted allyl terminus to yield allylic amines 173. The (/j2-crotyl acetate) Fe(CO)4 complex 174, on the other hand, does not react with morpholine184. 

C. Crotyl diazoacetate. A solution of 10.0 g. (0.038 mole) of the />-toluenesulfonylhydrazone of glyoxylic acid chloride in 100 ml. of methylene chloride is cooled in an ice bath. Crotyl alcohol (2.80 g. or 0.038 mole) (Note 7) is added to this cold solution, and then a solution of 7.80 g. (0.077 mole) of redistilled triethyl-amine (b.p. 88.5-90.5°) in 25 ml. of methylene chloride is added to the cold reaction mixture dropwise and with stirring over a 20-minute period. During the addition a yellow color develops in the reaction mixture and some solid separates near the end of the addition period. The resulting mixture is stirred at 0° for 1 hour and then the solvent is removed at 25° under reduced pressure with a rotary evaporator. A solution of the residual dark orange liquid in approximately 200 ml. of benzene is thoroughly mixed with 100 g. of Florisil (Note 8) and then filtered. The residual Florisil, which has adsorbed the bulk of the dark colored by-products, is washed with two or three additional portions of benzene of such size that the total volume of the combined benzene filtrates is 400-500 ml. This yellow benzene solution of the diazoester is concentrated under reduced pressure at 25° with a rotary evaporator, and the residual yellow liquid is distilled under reduced pressure. (Caution This distillation should be conducted in a hood behind a safety shield) (Note 9). The diazo ester is collected as 2.20-2.94 g. (42-55%) of yellow liquid, b.p. 30-33° (0.15 mm.), n T) 1.4853 - 1.4856 (Note 10). 

It has been shown that the tri-n-butyltin group can control the diastereoselection of an aza-[2,3]-Wittig rearrangement, and the silicon-assisted aza-[2,3]-Wittig rearrangement of crotyl-type amines has been used to furnish each diastereoisomer of the... 

When dendritic catalyst 2 was applied in the allylie amination of crotyl acetate and piperidine in the CFMR, a similar rapid deaetivation of the eatalyst was observed. 

Fig. 5. Application of dendrimeric ligand 4 in the allylic amination of crotyl acetate and piperidine using a CFMR (% conversion of crotyl acetate in the product stream vs substrate flow), (a) P/Pd = 2, (b) P/Pd = 4, Koch MPF-60 NF membrane, molecular weight cut-off = 400 Da) )18b).

In the presence of a Lewis acid or fluoride ion, imines react with allylsilane to yield the homoallylic amines with high stereoselectivity119,120. Thus, treatment of N-galactosylaldimine 81 with allylsilane in the presence of excess of SnCU yields the corresponding allylated product 82 (equation 54). It is noted that aliphatic aldimines do not react under these conditions. Fluoride ion promoted crotylation of aldimines proceeds in a regiospecific and diasteroselective manner121. A pentacoordinate silicate moiety is involved in this reaction. 

The resulting peripheral phosphine-functionalized dendrimers were used as a ligand in the palladium-catalyzed allylic amination of crotyl acetate in a CFMR. The active catalysts were prepared by mixing all three components the dendrimer, the phosphine ligand and a suitable palladium precursor [(crotyl)PdCl]2. The catalytic activity and selectivity of 16 in a batch process... 

Pd-catalyzed allylic amination of crotyl acetate by piperidine, while exhibiting a reduced rate as is commonly observed for heterogenized systems (90% conversion achieved after 30 min compared with 5 min for the homogeneous system). Interestingly, the catalyst could be recycled three times via a simple filtration step. Subsequently, the catalyst was separated from the support and the support was uploaded with hydroformylation catalysts. 

Table 7 Results of the Pd-catalyzed allylic amination of crotyl acetate and piperidine, comparing the supramolecular dendrimeric catalyst with the corresponding monomer3...

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