反应详情

A related strategy was applied to the synthesis of (±)-(cis-3-aminocyclopentanyl)methylphosphinic acid (Scheme 3). However, in this synthesis, a Mitzanobu reaction was performed at the start of the sequence on isopropyl (±)-(3-hydroxycyclopentenyl)methylphosphinate (3) to yield (±)-isopropyl (3-aminocyclopentenyl)methylphosphinate (8). The amine was then protected as the t-butyloxycarbonylamide (BOC) (9) which provided the steric bulk to direct the approach of the hydrogen. The hydrogenation was carried out over PtO2 at 40 psi affording the (±)-cis-N-butyloxycarbonyl cyclopentane (10) in quantitative yield and a diastereomeric excess of 95:5 cis:trans. The minor diastereoisomer could be separated by silica gel chromatography.

1. customprovided the steric bulk