Oxidation catalysts called NewTAMLs, macrocyclic complexes with TAML carbonamido-N donors replaced by more nucleophile-resistant binders, sulfonamido-N, for example, [Fe{4-NO 2 C 6 H 3 -1,2-(NCOCMe 2 NSO 2 ) 2 CHMe}] − (5d), deliver record-setting technical performance parameters (TPPs) for functional peroxidase mimicry. NewTAMLs were designed to test the previously discounted hypothesis that nucleophilic decay of carbonamido-N iron chelators is TAML catalyst lifetime-limiting and, for precautionary reasons, to escape fluorine in the best-performing TAML (1c) for catalyzing ultradilute water purification by H 2 O 2 . Replacing two of four TAML carbonamides with less σ-donating sulfonamides in 5 was found to more than compensate for eliminating 1c's F-substituents to increase substrate oxidation rates and, following the discovery and parametrization of an additional decomposition mechanism, to alter catalyst degradation rates protectively. At pH 7 in less than 5 min, the best-performing NewTAML 5d activates H 2 O 2 to eliminate the β-blocker drug and sentinel micropollutant (MP) propranolol to the limit of UPLC detection under very dilute starting conditions that pass through the ultradilute regime (≤2 ppb): [5d] = 100 nM (∼60 ppb), [propranolol] = 53 nM (15.6 ppb), [H 2 O 2 ] = 330 μM (11.2 ppm). This is ca. 10 times faster than 1c/H 2 O 2 under comparable conditions giving an important advance in the real-world potential for time-, concentration-, and cost-sensitive MP water treatments. The separate decomposition mechanism involves carbon acids bridging the two sulfonamides, a discovery that expands design control over operating NewTAML lifetimesthese features we have named "kill switches" are analyzed for impacts on catalytic function, process control, and sustainable design. Mouse uterotrophic assays show no low-dose adverse effects (lodafs) for the prototype NewTAML (5a) or for the process solution from the 5a/H 2 O 2 destruction of the contraceptive pill estrogen, ethinyl estradiol (EE2), a potent MP. The multidisciplinary catalyst design protocol that led to NewTAMLs is presented graphically to highlight how five key sustainability performancestechnical, cost, health, environmental, fairnessare being optimized together for sustainable oxidation catalysis and water treatment. The results validate the "bioinspired" descriptor and the name sustainable ultradilute oxidation catalysis (SUDOC) for this emerging field while highlighting to chemists that dealing with the lodafs and locafs (low-concentration adverse effects) of everyday−everywhere chemicals is essential for sustainability.

The conformational preferences of 28 sterically and electronically diverse N-aryl amides were determined using density functional theory (DFT), using the B3LYP functional and 6-31G­(d) basis set. For each compound, both the cis and trans conformers were optimized, and the difference in ground state energy calculated. For six of the compounds, the potential energy surface was determined as a function of rotation about the N-aryl bond (by 5° increments) for both cis and trans conformers. A natural bond orbital (NBO) deletion strategy was also employed to determine the extent of the contribution of conjugation to the energies of each of the conformers. By comparing these computational results with previously reported experimental data, an explanation for the divergent conformational preferences of 2° N-aryl amides and 3° N-alkyl-N-aryl amides was formulated. This explanation accounts for the observed relationships of both steric and electronic factors determining the geometry of the optimum conformation, and the magnitude of the energetic difference between cis and trans conformers: except under the most extreme scenarios, 2° amides maintain a trans conformation, and the N-bound arene lies in the same plane as the amide unless it has ortho substituents; for 3° N-alkyl-N-aryl amides in which the alkyl and aryl substituents are connected in a small ring, trans conformations are also favored, for most cases other than formamides, and the arene and amide remain in conjugation; and for 3° N-alkyl-N-aryl amides in which the alkyl and aryl substituents are not connected in a small ring, allylic strain between the two N-bound substituents forces the aryl substituent to rotate out of the plane of the amide, and the trans conformation is destabilized with respect to the cis conformation due to repulsion between the π system of the arene and the lone pairs on the oxygen atom of the carbonyl. The cis conformation is increasingly more stable than the trans conformation as electron density is increased on the arene because the more electron-rich arenes adopt a more orthogonal arrangement, increasing the interaction with the carbonyl oxygen, while simultaneously increasing the magnitude of the repulsion due to the increased electron density in the π system. The trans conformation is favored for 2° amides even when the arene is orthogonal to the amide, in nearly all cases, because the C–N–C bond angle can expend at the expense of the C–N–H bond angles, while this is not favorable for 3° amides.

The synthesis and functionalization of the parent 1,3-benzothiaphosphole is reported. The phosphole could not be isolated, but the compound could be manipulated in solution to produce several new phosphorus compounds. Metalation of the 2-position using lithium diisopropylamide proceeded smoothly according to 31 P NMR spectroscopy, and quenching with trimethylsilyl chloride resulted in the desired 2-(trimethylsilyl)-1,3-benzothiaphosphole. The PC bond of the thiaphosphole was also explored as a dienophile in Diels−Alder reactions with isoprene, 2,3-dimethylbutadiene, 2,3dibenzylbutadiene, and cyclopentadiene. The fused-ring structures were fully characterized, and a solid-state molecular structure of the 2,3-dimethylbutadiene cycloadduct was obtained. Residual dipolar coupling (RDC) NMR experiments were used to assign major and minor products for the isoprene and cyclopentadiene adducts.