170899-15-7

Upstream product

• 79026-61-2 (R)-3-benzyloxy-2-methylpropanal 
• 171011-57-7 Acetic acid 2-tributylstannanyl-penta-2,3-dienyl ester 

Downstream Products

• 207226-56-0 {(R)-2-[(4R,5R,6R)-6-((R)-2-Benzyloxy-1-methyl-ethyl)-2,2,5-trimethyl-[1,3]dioxan-4-yl]-propoxy}-tert-butyl-diphenyl-silane 
• 207226-54-8 (2R,3R,4R,5R,6R)-1-Benzyloxy-7-(tert-butyl-diphenyl-silanyloxy)-2,4,6-trimethyl-heptane-3,5-diol 
• 207461-76-5 (2R,3R,4S,5R,6R)-7-Benzyloxy-2,4,6-trimethyl-heptane-1,3,5-triol 
• 207226-59-3 (E)-(4S,5S,6R)-7-Benzyloxy-5-methoxymethoxy-4,6-dimethyl-hept-2-en-1-ol 
• 207226-61-7 (2R,3R,4S,5R,6R)-7-Benzyloxy-5-methoxymethoxy-2,4,6-trimethyl-heptane-1,3-diol 
• 81470-85-1 (R)-2-{(4R,5R,6R)-6-[(R)-2-(tert-Butyl-diphenyl-silanyloxy)-1-methyl-ethyl]-2,2,5-trimethyl-[1,3]dioxan-4-yl}-propan-1-ol 

Relevant academic research and scientific papers

Synthesis of Stereopentad Subunits of Zincophorin and Rifamycin-S through Use of Chiral Allenyltin Reagents

The anti,anti adduct 3, from addition of the allenic stannane (P)-2 to the a-methyl-β-OBn aldehyde (S)-1 promoted by SnCl4, was converted to the stereopentad 6 by a sequence involving reduction to the (E)-allylic alcohol with Red-Al, Sharpless asymmetric epoxidation, and addition of the higherorder methyl cyanocuprate to the derived epoxide 5. Stereopentad 6 was converted to the acetonide acetal 15, an intermediate in Danishefsky's synthesis of zincophorin. By a similar sequence, adduct ent-4 was converted, via diol 19, to stereopentad 22, an intermediate in Kishi's synthesis of rifamycin-S. An alternative route to diol 19 was achieved from the MOM-protected derivative 28 of epoxy diol 18.

Comparative Studies on the Synthesis of an anti,syn Stereotriad with Chiral Allenylstannane and Allenylindium Reagents

Addition of the chloroallenylstannane derived from the Bu3Sn allene (S)-2 and SnCl4 to nonracemic α-methyl-β-oxygenated aldehyde 1a afforded mixtures of anti,syn and anti,anti adducts 3a and 3b. When InCl3 was employed in the transmetalation of allenylstannane (S)-2, a mixture of adducts 3a and ent-3b was produced. Experiments with the β-ODPS aldehydes 1b and 5 showed that InBr3 and InI3 yield a transient InXn species from allenylstannane (S)-2 with mainly retention of configuration. In contrast, transmetalation of (S)-2 with SnCl4 or BuSnCl3 affords an intermediate allenyl species of inverted configuration. The (S)-2/BuSnCl3 reagent showed high enantio- and diastereoselectivity in addition to aldehydes 1a, 1b, and 5. The (S)-2/InBr3 or InI3 reagent, while somewhat less selective, afforded enantiomeric or diastereomeric adducts.

Synthesis of syn,syn; anti,syn; syn,anti; and anti,anti Stereotriads from a Single Pair of Enantiomeric Reagents

The stannanes (S)-1a, (R)-1b, and (S)-1c add to (S)- and (R)-2-methyl-3-(benzyloxy)propanal ((S)-2 and (R)-2) to afford the syn,syn (BF3*OEt2 promotion), syn,anti (MgBr2*OEt2 promotion), anti,anti (SnCl4-derived reagent in CH2Cl2), and anti,syn (SnCl4-derived reagent in hexane) stereotriad adducts 3, 4, 6, and 7.