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Bis(imino)pyridine (BIP) iron alkoxide complexes act as catalysts to efficiently polymerize N-carboxyanhydrides (NCAs), including γ-benzyl-l-glutamate NCA (BLG-NCA) and sarcosine NCA (Sar-NCA), at room temperature. Reaction rates were greatly enhanced with the addition of mild Lewis acids, such as [CoCp2][BArF24], which work cooperatively with the iron-based catalysts to facilitate NCA polymerization. The reactivity of (2,6MeBIP)FeOCH2C(CH3)3with Sar-NCA was combined with its known reactivity for ε-caprolactone polymerization to form diblock and triblock copoly(ester-b-peptides) through sequential addition of lactone and NCA monomers. Redox-switchable polymerization reactions were developed by iteratively exposing the catalyst to redox reagents and Sar-NCA or cyclohexene oxide. The orthogonal reactivity demonstrated by the catalyst in its oxidized and reduced states led to the synthesis of diblock and triblock copoly(ether-b-peptides). Polyether segments were synthesized with the catalyst in its oxidized state, while the polyamide segments were synthesized with the catalyst in its reduced state. Both copolymerization reactions developed here are rare examples where NCA polymerization reactions can be combined with other ring-opening polymerization reactions to make copolymers containing polypeptides and other functional monomers.

The critical look at hospice care by Felicia Ackerman in Vol. 6 of the Cambridge Quarterly requires a response, since the author presents her view as having major implications for health policy. As a healthcare executive with over 25 years experience, and as a spokesperson for both my own program and others in the National Hospice Work Group, twelve of the nation's largest nonprofit hospices, I submit that her analysis of hospice care is naive. Ackerman's lack of practical understanding concerning the care of the terminally ill results in a discussion that misses the key policy issues.