128693-47-0

Upstream product

• 90865-70-6 [3R]-4-Benzyloxy-3-methylbutanal 
• 132364-35-3 (E)-4-Piperidino-2-methylbut-2-en-1-ol 
• 90809-27-1 4-<(1E,3R)-4-(Benzyloxy)-3-methylbut-1-enyl>morpholine 
• 90809-16-8 4-<(E)-4-(Benzyloxy)-3-methylbut-2-enyl>morpholine 
• 90809-25-9 (1E,3R)-4-(Benzyloxy)-N,N-dibutyl-3-methylbut-1-enylamine 
• 90809-14-6 (E)-4-(Benzyloxy)-N,N-dibutyl-3-methylbut-2-enylamine 
• 132364-34-2 (E)-4-(Diethylamino)-2-methylbut-2-en-1-ol 
• 1838-94-4 isoprene epoxide 
• 91458-94-5 (1E,3R)-4-(Benzyloxy)-N,N-diethyl-3-methylbut-1-enylamine 
• 100-39-0 benzyl bromide 
• 138485-77-5 (S)-4-Benzyloxy-2-tert-butoxycarbonyl-3-methylbutansaeure-tert-butylester 
• 90809-15-7 1-<(E)-4-(Benzyloxy)-3-methylbut-2-enyl>piperidine 
• 90809-26-0 1-<(1E,3R)-4-(Benzyloxy)-3-methylbut-1-enyl>piperidine 
• 90809-13-5 (E)-4-(Benzyloxy)-N,N-diethyl-3-methylbut-2-enylamine 

Downstream Products

• 132364-40-0 (3R)-4-(Benzyloxy)-3-methyl-N-<(R)-α-methyl-4-nitrobenzyl>butanamide 
• 248916-33-8 (1R)-3-methyl-2-cyclohexenyl (3R)-4-benzyloxy-3-methylbutanoate 
• 1041325-28-3 [4S,3(3R)]-3-(4-benzyloxy-3-methylbutanoyl)-4-phenyl-2-oxazolidinone 
• 248916-54-3 (2S,3R)-4-benzyloxy-3-methyl-2-((1S)-1-methyl-2-cyclohexenyl)butanoic acid 
• 248916-34-9 (2R,3R)-4-benzyloxy-3-methyl-2-((1S)-1-methyl-2-cyclohexenyl)butanoic acid 

Relevant academic research and scientific papers

A new synthesis of (S)-β-methyl-γ-butyrolactone and (S)-4-benzyloxy-3-methylbutanoic acid

A stereoselective synthesis of (S)-β-methyl-γ-butyrolactone [(S)-4,5-dihydro-4-methyl-2(3H)-furanone, 1] and of (S)-4-benzyloxy-3-methylbutanoic acid (2) is described. Both compounds are prepared starting from inexpensive L-ethyl lactate with overall yields of 26% and 30%, respectively. The products are valuable chiral building blocks.

Synthesis of Optically Active Bifunctional Isoprenoid Building Blocks by Rhodium(I)-Catalyzed Asymmetric Allylamine to Enamine Isomerization

The application of the known asymmetric allylamine to enamine isomerization methodology to bifunctional C5-isoprenoid allylic amines of types IId and IIe (Scheme 1) is described.It is shown that a number of such substrates can be isomerized with enantioselectivities of >90percent ee using cationic RhI complexes containing (6,6'-dimethylbiphenyl-2,2'-diyl)bis(diphenylphosphine) (BIPHEMP; 9) as asymmetry-inducing ligand (Scheme 2, Tables 1 and 2).Synthetically most useful is the isomerization of the benzyloxy derivative 10a into the (E)-enamine 11a.This isomerization proceeds with very high enantioselectivity (98-99percent ee) and affords, after enamine hydrolysis, the optically active 4-(benzyloxy)-3-methylbutanals ((R)- or (S)-12) in chemical yields of ca. 90percent.In conjunction, a short synthetic route to the starting material 10a has been developed which has a Pd-catalyzed amination of isoprene epoxide (30) as the key step.Thus, convenient and practical access to the optically active aldehydes (R)- and (S)-12 is now at hand.These aldehydes are useful optically active bifunctional building blocks for isoprenoid homologation.