Supporting Transformation through Delivery System Reform Incentive Payment Programs: Lessons from New York State.

The New York Delivery System Reform Incentive Payment (DSRIP) waiver was viewed as a prototype for Medicaid and safety net redesign waivers in the Affordable Care Act (ACA) era. After the insurance expansions of the ACA were implemented, it was apparent that accountability, value, and quality improvement would be priorities in future waivers in many states. Despite New York's distinct provider relationships, previous coverage expansions, and local and state politics, it is important to understand the key characteristics of the waiver so that other states can learn how to better incorporate value-based arrangements into future waivers or attempts to limit spending under proposed Medicaid per-capita caps or block grants. In this article, we examine the New York DSRIP waiver by drawing on its design, early experiences, and evolution to inform recommendations for the future renewal, implementation, and expansion of redesigned or transformational Medicaid waivers.

Co(III) imidos exhibiting spin crossover and C-H bond activation.

The reaction of ((Ar)L)Co(py) with (t)BuN(3) afforded the isolable three-coordinate Co-imido complex ((Ar)L)Co(N(t)Bu), which is paramagnetic at room temperature. Variable-temperature (VT) (1)H NMR spectroscopy, VT crystallography, and magnetic susceptibility measurements revealed that ((Ar)L)Co(N(t)Bu) undergoes a thermally induced spin crossover from an S = 0 ground state to a quintet (S = 2) state. The reaction of ((Ar)L)Co(py) with mesityl azide yielded an isolable S = 1 terminal imido complex that was converted into the metallacycloindoline ((Ar)L)Co(κ(2)-NHC(6)H(2)-2,4-Me(2)-6-CH(2)) via benzylic C-H activation.

Trigonal Mn3 and Co3 clusters supported by weak-field ligands: a structural, spectroscopic, magnetic, and computational investigation into the correlation of molecular and electronic structure.

Transamination of divalent transition metal starting materials (M(2)(N(SiMe(3))(2))(4), M = Mn, Co) with hexadentate ligand platforms (R)LH(6) ((R)LH(6) = MeC(CH(2)NPh-o-NR)(3) where R = H, Ph, Mes (Mes = Mesityl)) or (H,Cy)LH(6) = 1,3,5-C(6)H(9)(NHPh-o-NH(2))(3) with added pyridine or tertiary phosphine coligands afforded trinuclear complexes of the type ((R)L)Mn(3)(py)(3) and ((R)L)Co(3)(PMe(2)R')(3) (R' = Me, Ph). While the sterically less encumbered ligand varieties, (H)L or (Ph)L, give rise to local square-pyramidal geometries at each of the bound metal atoms, with four anilides forming an equatorial plane and an exogenous pyridine or phosphine in the apical site, the mesityl-substituted ligand ((Mes)L) engenders local tetrahedral coordination. Both the neutral Mn(3) and Co(3) clusters feature S = (1)/(2) ground states, as determined by direct current (dc) magnetometry, (1)H NMR spectroscopy, and low-temperature electron paramagnetic resonance (EPR) spectroscopy. Within the Mn(3) clusters, the long internuclear Mn-Mn separations suggest minimal direct metal-metal orbital overlap. Accordingly, fits to variable-temperature magnetic susceptibility data reveal the presence of weak antiferromagnetic superexchange interactions through the bridging anilide ligands with exchange couplings ranging from J = -16.8 to -42 cm(-1). Conversely, the short Co-Co interatomic distances suggest a significant degree of direct metal-metal orbital overlap, akin to the related Fe(3) clusters. With the Co(3) series, the S = (1)/(2) ground state can be attributed to population of a single molecular orbital manifold that arises from mixing of the metal- and o-phenylenediamide (OPDA) ligand-based frontier orbitals. Chemical oxidation of the neutral Co(3) clusters affords diamagnetic cationic clusters of the type [((R)L)Co(3)(PMe(2)R)(3)](+). Density functional theory (DFT) calculations on the neutral (S = (1)/(2)) and cationic (S = 0) Co(3) clusters reveal that oxidation occurs at an orbital with contributions from both the Co3 core and OPDA subunits. The predicted bond elongations within the ligand OPDA units are corroborated by the ligand bond perturbations observed by X-ray crystallography.

Catalytic C-H bond amination from high-spin iron imido complexes.

Dipyrromethene ligand scaffolds were synthesized bearing large aryl (2,4,6-Ph(3)C(6)H(2), abbreviated Ar) or alkyl ((t)Bu, adamantyl) flanking groups to afford three new disubstituted ligands ((R)L, 1,9-R(2)-5-mesityldipyrromethene, R=aryl, alkyl). While high-spin (S=2), four-coordinate iron complexes of the type ((R)L)FeCl(solv) were obtained with the alkyl-substituted ligand varieties (for R=(t)Bu, Ad and solv=THF, OEt(2)), use of the sterically encumbered aryl-substituted ligand precluded binding of solvent and cleanly afforded a high-spin (S=2), three-coordinate complex of the type ((Ar)L)FeCl. Reaction of ((Ad)L)FeCl(OEt(2)) with alkyl azides resulted in the catalytic amination of C-H bonds or olefin aziridination at room temperature. Using a 5% catalyst loading, 12 turnovers were obtained for the amination of toluene as a substrate, while greater than 85% of alkyl azide was converted to the corresponding aziridine employing styrene as a substrate. A primary kinetic isotope effect of 12.8(5) was obtained for the reaction of ((Ad)L)FeCl(OEt(2)) with adamantyl azide in an equimolar toluene/toluene-d(8) mixture, consistent with the amination proceeding through a hydrogen atom abstraction, radical rebound type mechanism. Reaction of p-(t)BuC(6)H(4)N(3) with ((Ar)L)FeCl permitted isolation of a high-spin (S=2) iron complex featuring a terminal imido ligand, ((Ar)L)FeCl(N(p-(t)BuC(6)H(4))), as determined by (1)H NMR, X-ray crystallography, and (57)Fe Mössbauer spectroscopy. The measured Fe-N(imide) bond distance (1.768(2) Å) is the longest reported for Fe(imido) complexes in any geometry or spin state, and the disruption of the bond metrics within the imido aryl substituent suggests delocalization of a radical throughout the aryl ring. Zero-field (57)Fe Mössbauer parameters obtained for ((Ar)L)FeCl(N(p-(t)BuC(6)H(4))) suggest a Fe(III) formulation and are nearly identical with those observed for a structurally similar, high-spin Fe(III) complex bearing the same dipyrromethene framework. Theoretical analyses of ((Ar)L)FeCl(N(p-(t)BuC(6)H(4))) suggest a formulation for this reactive species to be a high-spin Fe(III) center antiferromagnetically coupled to an imido-based radical (J = -673 cm(-1)). The terminal imido complex was effective for delivering the nitrene moiety to both C-H bond substrates (42% yield) as well as styrene (76% yield). Furthermore, a primary kinetic isotope effect of 24(3) was obtained for the reaction of ((Ar)L)FeCl(N(p-(t)BuC(6)H(4))) with an equimolar toluene/toluene-d(8) mixture, consistent with the values obtained in the catalytic reaction. This commonality suggests the isolated high-spin Fe(III) imido radical is a viable intermediate in the catalytic reaction pathway. Given the breadth of iron imido complexes spanning several oxidation states (Fe(II)-Fe(V)) and several spin states (S=0→(3)/(2)), we propose the unusual electronic structure of the described high-spin iron imido complexes contributes to the observed catalytic reactivity.

Unusual electronic structure of first row transition metal complexes featuring redox-active dipyrromethane ligands.

Transition metal complexes (Mn --> Zn) of the dipyrromethane ligand, 1,9-dimesityl-5,5-dimethyldipyrromethane (dpm), have been prepared. Arylation of the dpm ligand alpha to the pyrrolic nitrogen donors limits the accessibility of the pyrrole pi-electrons for transition metal coordination, instead forcing eta(1),eta(1) coordination to the divalent metal series as revealed by X-ray diffraction studies. Structural and magnetic characterization (SQUID, EPR) of the bis-pyridine adducts of (dpm)Mn(II)(py)(2), (dpm)Fe(II)(py)(2), and (dpm)Co(II)(py)(2) reveal each divalent ion to be high-spin and pseudotetrahedral in the solid state, whereas the (dpm)Ni(II)(py)(2) is low-spin and adopts a square-planar geometry. Differential pulse voltammetry on the (dpm)M(II)(py)(2) series reveals a common two-electron oxidation pathway that is entirely ligand-based, invariant to the divalent metal-bound, its geometry or spin state within the dpm framework. This latter observation indicates that fully populated ligand-based orbitals from the dpm construct lie above partially filled metal 3d orbitals without intramolecular redox chemistry or spin-state tautomerism occurring. DFT analysis on this family of complexes corroborates this electronic structure assignment, revealing that the highest lying molecular orbitals are completely ligand-based. Chemical oxidation of the deprotonated dpm framework results in the four-electron oxidation of the dipyrrolide framework, although this oxidation product was not observed either in the electrochemical or chemical oxidation of the (dpm)M(II)(py)(2) complexes.

C-H bond amination from a ferrous dipyrromethene complex.

In this Communication, we report an intramolecular C-H bond amination reaction of a dipyrromethene ferrous complex with organic azides. Monitoring of the spectral changes (variable-temperature NMR and UV-vis) of the Fe(II) complex reveals no buildup of an intermediate during conversion of the starting material into the nitrene-inserted product. The rate-determining step appears to be azide addition to the 14-electron Fe(II) complex, hinting at the potential that these and related platforms may have to effect atom- and group-transfer processes.